Category Archives: Quantum Physics
Scientists predicted that the coronavirus death rate would fall over time, but instead it doubled. Here’s why – Business Insider India
Many countries' coronavirus curves are flattening, at least for now.
Yet somehow, the global case-fatality rate has increased significantly since March, when it was around 3.4%. The rate was 5.8% on Tuesday, according to tallies from the World Health Organization, and it hovered around 7% from mid-April through May.
But it seems testing has not increased enough to result in a significant downward trajectory.
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Some epidemiologists say that because death rates are so heavily influenced by testing and delays in reported cases and deaths, they're simply not a reliable measure of the virus's toll over time.
In general, the more cases that are included in the data including people with mild or no symptoms the lower the death rate.
In that sense, case-fatality rates "are more a measure of how much testing and case finding you do," John Edmunds, a professor of infectious-disease modeling at the London School of Hygiene & Tropical Medicine, told Business Insider.
South Korea, which has tested more than 1 million people, far outpaced other countries in early case detection and contact tracing. While US labs waited for weeks for instructions on how to fix faulty test kits in February, South Korea was testing tens of thousands of people.
Limited testing in other countries, like Sweden and the US, make their case counts inaccurately low. In the US, experts think we need to multiply the official confirmed case count by 10 to get an accurate estimate of true infections nationwide.
When countries miss many mild cases, deadly cases seem like a higher proportion of infections than they really are. Countries like the US and Sweden, therefore which have case-fatality rates of 5.7% and 10.3%, respectively could be inflating the global death rate.
"Mortality will spuriously spike when cases are decreasing," William Hanage, an epidemiologist at Harvard's TH Chan School of Public Health, told Business Insider. "The reason is that you are seeing the deaths from when the epidemic was expanding, or at least more intense than it is now, while your total case counts are up to the present."
The fact that death tolls lag behind case counts can briefly create a very high death rate. That's what seems to have happened in April and May. (And limited testing can magnify that effect.)
That math suggests the virus has killed roughly 1% of the people who tested positive four weeks ago. But again, since that doesn't include many people with mild or asymptomatic cases, the true proportion of people who die after being infected is probably much lower.
That's far lower than what case-fatality rates suggest, but it's still 13 times higher than the death rate of the seasonal flu.
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Armijo: The absolute power of love | VailDaily.com – Vail Daily News
There is a lot to digest that is currently taking place in our world. If we only follow the news, we may believe we are living the apocalypse. Lets address the current situation of racism and hate.
First, we must understand that those who are putting forth hate and racism are merely projecting their insecurities upon others. We do not need to feel bad for them (its OK to take pity on them) but we do need to lead them through better examples.
Dr. Martin Luther King Jr. stated it perfectly when he said, Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that.
Love is something that was often seen as a weakness for many years in our society. People who preached love were seen as outliers or New Age practitioners with their hippy insights. However, some of the most well-known and well-respected leaders lead through love. A true leader understands the basic foundation of all humanity which is we are all connected.
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Referring back to Quantum Physics, we understand that everything in our universe is energy and is connected by energy. This energy can be beneficial to us or detrimental to our overall well-being and happiness. Love has been measured to vibrate at the highest frequency in our universe whereas hate vibrates on the lowest frequency.
This means very simply that hate can only be overcome by its polar opposite, which is love. Those with weak mindsets will always try to push harder against that which they do not like. This will always backfire for them because they are not working within the laws of the universe.
Imagine, if you will, a grid-like blanket of energy that is draped over everything here on this planet. This energetic grid connects each and every one of us to all things on this planet. Therefore, whatever we put out into the world will come back to us in some manner or another.
When we hate someone else or hurt them, we are literally hurting ourselves in the process. The only way we can achieve change in the midst of hate is to counter said hate with feelings of love. This is not an easy feat to accomplish but it is very effective.
Does this mean we have to go to those people spewing hate and violence and tell them we love them? Absolutely not. We can change the tide of what is taking place on this planet without the need to interact with these individuals.
In 1993, there was a study done in Washington D.C. on meditation and crime. It involved a group of people meditating (between 800 and 4,000 over the trial) from June 7 through July 30. At the time, Washington D.C. had one of the highest violent crime rates in the nation. The hypothesis of the study was to determine if a group of people meditating could lower the crime rate.
The researchers estimated the crime rate would be reduced by 20% just through meditation. The chief of police said it would take 20 inches of snow to drop the crime rate that much. The result was a 23% drop in violent crime during the time the meditations were taking place. The power we each contain is impressive but the power we have when we come together is nothing short of amazing.
If you feel helpless watching the events that are unfolding, dont. Do something constructive by keeping yourself in a positive state. Practice meditation (send me an email if you have questions), yoga, or start a gratitude journal. Just remain positive and, for goodness sake, turn off the news.
Understand that every person you meet is connected to you. We are all brothers and sisters, mothers, and fathers and we need to learn to treat each other as such. We are not programmed to notice a difference in skin color or facial features, these are things that are taught to us. We must come together through love and insist on creating a better, more sustainable world for our future generations because what we are experiencing right now is something that most of us would never want our children to experience.
Chad Armijo lives in Edwards and is the founder of http://www.chadarmijocoaching.com, Elev8te SEO, and creator of the Mind Muscle Mastery program. He holds two masters degrees from Colorado State University in Business Management and Adult Teaching. In addition, he is a Master Certified NLP Life/Business Success Coach and Certified Ericksonian Hypnotherapist as well as a Pilates instructor. Find him on Facebook (@lifecoachingvail) or Instagram (@carmijo12) or email him at chadarmijocoaching@gmail.com.
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Could Every Electron in the Universe Be the Same One? – Interesting Engineering
You probably remember electrons from science class. They're stable subatomic particles that have a negative electrical charge. They're found in atoms and are the primary carrier of electricity in solid materials. But, what you probably haven't heard of, is the idea that each and every electron in existence... is actually the exact same electron.
This theory states that every electron in the universe is actually one particle that continually travels backward and forward through time. There is a lot of complicated math involved, but it does solve some of quantum physics biggest unanswerable questions.
The theory was first thought up by John Archibald Wheeler, a theoretical physicist who worked on the hydrogen bomb at Los Alamos and later taught at Princeton. He is largely known for reviving interest in general relativity in the 1940s and 1950s.
Like many quantum theories, the idea that every electron is the same electron, known as the One Electron Theory, is more of a thought experiment than a theory.
So let's break it down.
One of the biggest reasons that this thought experiment was proposed by Wheeler is that each and every electron looks exactly the same. They all have the same mass and the same electric charge.
This ultimately means that it's impossible to tell electrons apart at all. So, it's not surprising that Wheeler thought up the idea that if all electrons look the same and act the same, then maybe they are the same electron.
RELATED: PHYSICISTS JUST MADE ELECTRONICS THAT SWITCH ON AND OFF AT THE SPEED OF LIGHT
Proposing that the entire universe contains just one electron may not seem all that absurd, when we consider that the only change would be to the idea of what an electron is. In practicality, everything would still function the same.
According to the One Electron theory, in the same way as an electron can be bounced around in space when hit with light, the electron might also be able to bounce backward in time.The consequence of this is that electrons moving backwards in time are positrons, the antimatter component of electrons. So, not only are all electrons the same electron, but all positrons are also the same electron moving backward.
As a professor, Wheeler taught the now-famous physicist Richard Feynman, when he was a doctoral student. Feynman famously brought up Wheeler's theory when he accepted his Nobel Prize in 1965. Here's what Feynman said:
I received a telephone call one day at the graduate college at Princeton from Professor Wheeler, in which he said, "Feynman, I know why all electrons have the same charge and the same mass." "Why?" "Because, they are all the same electron!" And, then he explained on the telephone, "suppose that the world lines which we were ordinarily considering before in time and space - instead of only going up in time were a tremendous knot, and then, when we cut through the knot, by the plane corresponding to a fixed time, we would see many, many world lines and that would represent many electrons, except for one thing. If in one section this is an ordinary electron world line, in the section in which it reversed itself and is coming back from the future we have the wrong sign to the proper time - to the proper four velocities - and that's equivalent to changing the sign of the charge, and, therefore, that part of a path would act like a positron."
To many physicists, what Wheeler was proposing really didn't seem that absurd. Physicists were already working with the idea of electrons and positrons, Wheeler just proposed a way to connect every single one in existence simultaneously as a way of explaining why no one could tell the difference between them.
It is estimated that there are roughly 10 to the power of 80 atoms in the universe. If we ignore the fact that many atoms have more than one electron, we can simplify the number of electrons in the universe as around 10 to the power of 80.
Although electrons are treated as stable for theoretical purposes, theexperimental lower bound for theelectron'smeanlifetimeis often given as 6.61028years. Using this, we can get an idea of how this theory actually plays out.
The theory and these numbers imply that the one electron in existence has traveled through the universe1080times, each time taking460 septillion years. We can double these numbers for each time that the electron had to go back through time, which equates to the one electron in the One Electron Theory being 10105years old.
All of this is rather interesting to consider, but there's an issue at the root of this thought experiment.
If a single electron travels forward through time as an electron and backward through as a positron, that would mean that at any given point, thereshouldbe the same number of positrons as there are electrons.
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We know this is not true, and since that is the case, we can deduce with strong confidence that the One Electron Theory cannot hold.
It is likely that Wheeler knew this was the case all along. In his memoir, he writes:
"I knew, of course, that, at least in our corner of the universe, there are lots more electrons than positrons, but I still found it an exciting idea to think of trajectories in spacetime that could go unrestricted in any direction forward in time, backward in time, up, down, left, or right."
Wheeler was nearly certain that his thought experiment wasn't a reflection of actual quantum reality, but he did note that the idea that there aren't the same number of positrons as electrons is only true for our observable universe. It's possible that it isn't the case for the sum total of the universe.
At the end of the day, the One Electron Theory is a rather interesting thought experiment to ponder, even if physics isn't your jam. To think that it's theoretically possible,although highly unlikely, that a particle that exists everywhere throughout the universe is actually the same particle, traveling through time well, that's pretty cool.
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Could Every Electron in the Universe Be the Same One? - Interesting Engineering
These 8 Books Have the Power to Change Your Perspective on Life – Morocco World News
Books have positively affected human existence for centuries. Some are valuable for entertainment, others for intellectual stimulation, and some are so powerful they can effectively change your perspective on life.
If you are one of those people who do not make a habit of reading regularly, you might be missing out.
In addition to expanding your vocabulary and critical thinking skills, reading books helps you develop your thought processes, keeps your brain active, and helps you learn and understand any topic you can imagine.
Reading books puts you in other peoples shoes, which can help you view the world from others points of view, making you wiser and more empathetic. By exploring different perspectives on life, you are also likely to get to know yourself better.
These are some of the books you should check out if you are looking for life-changing and inspiring pages that will help you learn, shape, and develop your mind and who you want to be.
Awaken the Giant Within by Tony Robbins
Awaken the Giant Within is a book by the American author, public speaker, life coach, and philanthropist Anthony Jay Robbins. The pages guide you through his most effective strategies and techniques for mastering your emotions, your body, your relationships, your finances, and your life.
Robbins did not grow up in a privileged home. He made a decision to change his life, leading him to spend over 20 years researching and analyzing the differences between those who succeed and those who stay on the social ladders lower rungs.
The book is divided into four parts: Understanding your power, Taking control: The master plan, 7 days to remodel your life, and Awaken the giant within. Each part is rich in information and methods for personal development.
Thinking, Fast and Slow by Daniel Kahneman
Thinking, Fast and Slow is an international bestseller by the renowned psychologist and winner of the Nobel Prize in Economics, Daniel Kahneman. The author approaches human rationality and irrationality, decision-making factors, and other aspects of psychology in his sixth and most popular book.
This work takes you on a tour of the mind and the two systems that affect the way we think. One system is fast, intuitive, and emotional, while the other one is slower, more deliberative, and logical. Kahnemans analysis looks at how these two systems shape our judgment and all our decisions, from who we want to be to where we want to eat.
This book is a great help in understanding your mind, how and when to rely on intuition, and how you can benefit from slow thinking. The author offers insights, methods, and techniques on how to deal with decision making, concerning both your business and personal life.
Stumbling on Happiness by Daniel Gilbert
Stumbling on Happiness is a New York Times bestseller by the famous Harvard University psychology professor Daniel Gilbert. The author describes our brains ability to simulate and imagine biased predictions about the future, which can lead us to make wrong decisions and incorrect assumptions about ourselves.
The book involves the latest scientific research in psychology, cognitive neuroscience, philosophy, and behavioral economics.
It showcases what scientists have discovered in humans ability to predict the future and our beliefs regarding the accuracy of forethought, the tricks our brains play on us, as well as how to deal with inaccurate predictions and avoid them in the future.
Daniel Gilberts research on happiness demonstrates that happiness is not much affected by what happens in your life, but more with how you end up choosing to see and react to life events.
Spark! by John Ratey
The bestselling author John J. Ratey is an associate clinical professor of psychiatry at Harvard Medical School and an internationally recognized expert in neuropsychiatry. In his book Spark!, Ratey illuminates the fascinating connection between the body and the mind.
The book illustrates the importance and the benefits of exercise on improving job performance, mental health, and quality of life in general. It is filled with case studies that prove exercise is the best defense against many mental illnesses such as depression and ADD, as well as addiction, aggression, menopause, and Alzheimers.
Exercise can have a significant impact on your life, productivity, confidence, health, and happiness. This book definitely has the power to change your mind about daily exercise because of its many logical and well-evidenced arguments.
A Brief History of Time by Stephen Hawking
A Brief History of Time is a popular-science book on cosmology by one the greatest minds of our time, the late English theoretical physicist and cosmologist Stephen William Hawking.
In the book, Hawking explains some of the most complex concepts in physics and phenomena of the natural world in a language everyone can understand, aiming to bring knowledge to all on how our planet was created, where it exists in the universe, and where it is going.
With more than nine million copies in 40 languages sold worldwide, the book has become a classic work, used in many scientific writings.
Relativity and quantum mechanics are not easy subjects, but this book allows you to gain a better understanding of the subjects in simple terms. Hawking describes many scientists discoveries, how their thinking has changed throughout time, and what science may still bring in the future.
The Power of Now by Eckhart Tolle
The Power of Now is a self-help book by the spiritual teacher and bestselling author Eckhart Tolle. The book has been read by millions in 33 languages and is recognized as one of the most influential spiritual books of our time.
Eckhart Tolle uses simple language and clear writing to highlight the importance of living in the present moment and avoiding unproductive thoughts of the past or future.
With enthusiastic writing and an easy question-and answer-format to help guide readers, the self-help book will help you recognize that living in the present is the truest path to happiness and freedom.
The most common ego identifications have to do with possessions, the work you do, social status and recognition, knowledge and education, physical appearance, special abilities, relationships, person and family history, belief systems, and often also political, nationalistic, racial, religious, and other collective identifications. None of these is you, stresses a key passage from The Power of Now.
Mans Search for Meaning by Victor Frankl
Mans Search for Meaning is the memoir of Austrian neurologist, psychiatrist, and Holocaust survivor Victor Frankl. In his book, he describes his experience in Nazi death camps and the lessons he drew from that time for spiritual survival.
Mans Search for Meaning is a two-part account: The first half discusses Frankls experience at the concentration camps, and the second half consists of universally applicable lessons learned from Franks struggle.
The book presents Frankls philosophy on how we are in the best position to control and determine the meaning and purpose of our own life, even in the worst conditions.
On the Genealogy of Morality by Fredrick Nietzsche
On the Genealogy of Morality is a book by the famous German philosopher, cultural critic, composer, poet, philologist, and Latin and Greek scholar, Friedrich Wilhelm Nietzsche. This book is about the history and interpretation of ethics.
The work consists of a preface and three interrelated essays that expand and follow through on concepts Nietzsche presented in Beyond Good and Evil (1886).
In this book, Nietzsche expresses his belief that in every society there are the strong (the talented and intelligent) and the weak (the less talented and intelligent).
The strong adopt ethical beliefs that justify their place in life and entitlement to their privileged position, believing that they have earned what is theirs. The weak adopt other beliefs that justify their own position, feel that people deserve aid and charity, and believe that people should live for themselves rather than for the other.
The philosopher argues that all these beliefs converge in the corrupting and oppressing of society, as well as the suppression of important human characteristics such as creativity, innovation, ambition, and even happiness itself.
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These 8 Books Have the Power to Change Your Perspective on Life - Morocco World News
Some Information Regarding Medical Physics – – KUSI
June 2, 2020
Posted: June 2, 2020
Have you heard of physics? Medical Profession is one of the terms applied to make reference to scientific physics. It includes a vast range of issues that are related and the first rung on the ladder is really understanding that which medical physics will be.
This is a division of physics that includes the study of this nuclear and sub atomic degree in a framework of quantum physics. At the level exactly where contaminants interact with each other, it includes the study of science as a result.
Medical Profession has produce a method which could use several tools like x-ray technology to further analyze the internal organs and tissues of their body. This really can be an invaluable way of having useful information about the arrangement and functioning of the body.
For your sake of researchers, doctors and other wellness care staff, theres just really a tool which could produce imaging more easy. A tool called an optical coherence tomography is currently used for xray data acquisition that was quick and dependable.
Higher level technology similar to it will help to improve the healthcare sciences. Modern medical programs have improved better use of this tool treat sufferers and to help diagnose certain disorders. This implies far more correct and faster identification and remedy.
The human body is one. Physicists function with development and the research of medical technologies to make them more efficient, precise and potent. This can be definitely an intriguing area of physics thats remarkably popular now among folks.
The basic principle behind those apparatus are those that they use these very simple laws of mathematics. The theory behind that is centered on some proven and fundamental theories of math. Included in paraphrase checker online these are the thought. These entities have excellent significance in the field of medical physics. In order to get a better understanding of how these materials might make matters efficient, more efficient and more effective, you will find many materials which can be found the industry today which possess some properties that are outstanding. These materials may make technologies much more efficient and effective.
This is one of those fields which were https://www.westerntc.edu/online-writing-center made advances in using mathematics . Medi cal mathematics research helps in acquiring tools and many devices that can certainly help in paraphrasingservice.com/paraphrasing-sentences/ cutting the sum of time needed to identify and cure illnesses. It has lots of software that can make medicine more effective and productive.
In the last few decades, several of the devices are based on the principle of quantum physics. These fundamentals are all predicated on the fact that is made up of matter waves. That was and also this may be exactly precisely the exact very same matter that is utilised to make tools and electronics gizmos which produce life simpler.
Magnetic fields have been demonstrated to make certain types of energy. Inside this way, magnetic fields could be used in ways to create. Magnetic fields are used in these assist and also MRI devices in realizing the interior organs and tissues of the body.
Medical science is a branch as a way to obtain thoughts and theories that possess applications of physics that has made use of a number of their absolute most fundamental laws of mathematics. A great deal of methods and ways are traditionally used in this discipline to assist understand the structures and use of the body. These include scanning and this also technology can be a valuable part of modern-day medicine that will help know how diseases manifest themselves.
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Francesca Vidotto: The Quantum Properties of Space-Time – JSTOR Daily
For nearly a century, theoretical physicists have been grappling with a major foundational question: how does gravity work within quantum mechanicsthe field devoted to the behavior and properties of particles smaller than atoms? The answer could open the door to a so-called theory of everything, one that explains the nature of both large objects and small particles, thereby bridging the gap between two fundamental physical theories, Einsteins general relativity and quantum mechanics.
While there are many possible explanationsstring theory arguably the best knowntheoretical physicist Francesca Vidotto offers a theory that has the advantage of focusing on the specific question of quantum gravity: how gravity works on the quantum scale. Vidotto has spent much of her life unraveling and exploring this approach, which is called loop quantum gravity.
As Vidotto and fellow theoretical physicist Carlo Rovelli put it in their book, Covariant Loop Quantum Gravity, the problem with quantum gravity is simply the fact that the current theories are not capable of describing the quantum behaviour of the gravitational field. Many of us understand gravityone of natures four fundamental forcesas the force that drives the dance of planets around other massive, celestial bodies. As children, we learn that it is what keeps our own bodies from flying off into space. Scientists once envisioned gravity as a traditional force, with the power to pull, but now, they understand it as a distortion of space-time.
But gravity does not translate easily into the mathematical language of quantum physics. It does not readily quantize. According to Vidotto, loop quantum gravity may be the key to understanding exactly how it works.
A successful theoretical framework for quantum gravity would help unravel many mysteries, from the beginning of the universe to the centers of black holes. Being able to merge general relativitywhich works well on the cosmic scalewith quantum mechanicswhich explains the workings of the miniscule scalewould provide answers that have hitherto been out of reach. We cant yet observe what happens inside a black hole, but some theoretical physicists say quantum gravity could give us access to the mouths of these phenomena, where we know gravity is so great that it lets neither light nor matter escape.
Vidotto has been pondering questions like these since at least the age of 12, when she read Stephen Hawkings A Brief History of Time. Riding her bike across the cobbled streets of her hometown in Treviso, Italy, she was struck one sunny morning with the conviction that questions about time, physics, and the universe were the kinds of questions she wanted to think about for the rest of her life. And so she has, partnering with giants in the field like Rovelli, her frequent collaborator, on theories like loop quantum gravity and spin foam.
Here, Vidotto shares thoughts on spin foam theory, her obsession with primordial quantum fluctuations, and one good way to turn kids into future scientists. She spoke to me from her new home in London, Ontario, where she teaches physics at The University of Western Ontario.
* * *
What drew you to science, in general?
When I was a little girl, I thought I would become a ballet dancer, or something else. During my first year of school this wonderful woman, my primary school teacher, had a method of teaching science to us that is still the way in which I think science works.
I remember her taking us out into the garden on the first day of school and asking us to draw pictures of what we saw in the garden. She asked us to look at our drawings and brainstorm about questions that were arising. We had to vote for the favorite question in the class. The question we chose was, What are the rocks made of? For the rest of the year we kept on studying this question together. We were divided into small groups. We had to make hypotheses. We had to collect this information set. We had to falsify our hypotheses. And this was wonderful.
For me, the most interesting part was that it was a very democratic process, where we listened to what the other groups of children were saying. The final answer to that question was in fact a collection of all the answers that were not falsified. And thats where I saw a summary of the knowledge we had collected. So, every time I think about how to do science, what dynamics we put in place as scientists, the importance of listening to others and being free to possibly change our mindsthese are lessons I learned when I was six years old and its something I bring with me to my work today.
Sounds like a good way to get more kids interested in STEM.
I think its really important. There is a lot of attention these days to get people interested in science, but I think we really have to get children involved in this process, this very interactive, engaging process of learning so theyre interested in science as they grow older.
Why are there so few women in science? The most effective actions are when girls are really young. There are studies that show how stereotypes get ingrained when girls are just eight years old, so we have to do something before that.
Which space and time question is always top of mind?
Well, I have an obsession now that has stayed with me since I started doing my own research: primordial quantum fluctuations. [You can think of primordial quantum fluctuations as the initial conditions before galaxies, planets, the universe came to be]. Today we have an understanding that all the structures we see in our universe, galaxies, stars and so on, all originated from some small seeds in the beginning of our universe. Its a common understanding that this initial situation was of quantum origin. By running simulations where we include the presence of these fluctuations, we can recall where all the structures were that we now see.
We have a very good understanding of how big or which kind of fluctuation should be there, but we dont have a theory that really provides them from scratch, from the bottom. So the theory I work with, quantum gravity, is a very promising candidate for a theory that provides a description of the quantum properties of space-time. In particular, its a theory that is able to describe these fluctuations, the quantum fluctuations that characterize space-time in the more extreme regimes, like in the beginning of the universe.
So my obsession since the beginning of my research was to try to use this theory, try to use quantum gravity, to study these fluctuations. This has been a long journey, but we have come to some important advances using numerical techniques. Of course, there are many projects and sometimes, I have to put this question aside, but I think this is the dream that will stick with me: to see really how we can describe the beginning of our universe using these techniques.
What is the primary discovery of loop quantum gravitytheory?
Loop quantum gravity is a theory with the goal of describing the quantum properties of space-time. The main realization is the fact that, because space-time itself can be described as a geometry, geometrical quantities should appear with discrete values. So geometrical quantities are, for instance, area, volume, angle, and so on. If you try to measure these quantities at the fundamental level, you would see that they appear with only certain values and with jumps between those values. This is very similar to what happens in more familiar situations described by quantum mechanics. For example, when you study angular momentum in quantum mechanics, you discover that this property, if you try to measure it, comes only with certain values. And with jumps between them. This is the main discovery of loop quantum gravity, and everything stems from there.
Can you explain this idea ofspin foam theory, an idea youve worked on with Carlo Rovelli?
Spin foam is simply the path integral formulations of loop quantum gravity. [Path integral formulation is the mathematical theory for understanding all the possible paths a quantum particle can take to get from one point to another.]
So loop quantum gravity is about describing the quantum geometry of space-time. The discovery of Einstein is that space-time itself, the geometry itself, is not something inert; its a dynamical object. Its something that may evolve. Following this in loop quantum gravity, we want to describe how the gravitational field, the geometry, evolves, but in a quantum manner. The language in the quantum theory with which this is done is the path integral.
In quantum mechanics, for instance, you start with a particle. You see a particle at one point, and later you see the particle at another point. So you have an initial state with a particle in a given position and the final state with the particle in another position. Then you want to study what the probability is that the particle goes from one position to the other. In order to do that, you have to sum over all possible trajectories that the particle could have taken in order to go from that first position to the other. All these trajectories are the different possible paths the particle could have taken from the initial point to the final. Path integral is this idea that you have the sum of all possible paths.
Here in quantum gravity, what we do is study the probability to go from one state of the geometry to another state of the geometry. You have two states, but these two states represent a geometry, and you want to know what all the possible geometries are that interpolate from one to the other. In other words, all the possible configurations of the gravitational fields that take you from one configuration to the other.
This is spin foam. [Spin foam is a 2-dimensional model with labeled edges, vertices, and faces with the goal of describing the geometry of quantum spacetime. So named because it resembles a kind of foam.] It provides a concrete realization of how to compute this quantity, this sum of geometries. It tells you how geometry evolves, what the dynamics of the quantum gravitational field are.
There are a select few who propose a merger between the two camps: loop quantum gravity and string theory. Do you believe there is compatibility between the two?
On both sides, we are theoretical physicists, we have been trained in quantum field theory and in general relativity, and we are using these basic tools in our work. Many specific techniques used by the two communities are similar, even if this is not always recognized. If you look at how different people conduct research on loop quantum gravity, you will find a lot of different techniques. We use certain terms and if you just check in the physics literature for string theory, you will find the exact same terminology. This means that both communities are somehow using the same things, and I think we are converging on the realization that some tools, some mathematical tools, are very useful to both sides. But we have different perspectives on how to implement them.
You can think of string theory and loop quantum gravity as one emerging from the particle physics community and the other emerging from the general relativity community. One camp stresses the importance of preserving the techniques that come from particle physics, while the other community stresses the importance of preserving what we have learned from general relativity. But, if we want to write down a theory of quantum gravity, we have to converge at a certain point.
String theory doesnt really include a well-defined theory of quantum gravity. It was born to answer other questions, like unification of forces and naturalness and so on. As a by-product it was supposed to have a quantum theory of gravity in its belly. When evaluating string theory, you should be careful, because you have to be clear about what the questions are that you want to answer with that theory. With loop quantum gravity, it is easier, because loop quantum gravity is born to answer one question, that is, How do we quantize gravity? Its a bit more of a humble question with respect to the other ones. I also think that because the question is more precise, we have been most successful with respect to that particular goal.
One fundamental property of the loop quantum gravity theory is that it allows for black holes to transition into white holes, which are the opposites of black holes, spitting out matter and energy, as opposed to consuming everything.
Oh, well, yes. The fundamental property is the fact that space-time is quantized, where you have fundamental grains of space-time. But this also has a counterpart, the fact that curvature is bounded. This means that the singularities that appear in general relativity are resolved in a quantum theory of gravity. Applied to the early universe, in cosmology there is a big bounce. The same thing happens in the center of a black hole.
Instead of having a singularity in the center, we just have a region that is very, very dense. When such a high density is reached, an effective quantum force appears like a repulsion that prevents the collapse of the black hole from continuing and triggers a new expanding phase that corresponds to a white hole. The idea that you can have a transition from a black hole to a white hole was something explored in the past, in the form of the Einstein-Rosen bridge [aka wormhole]. But the idea was that you would end up being in another region of space-time.
The insight that changes the picture is the possibility to have a transition to a white hole within our universe. Imagine you have some matter that starts collapsing, gets more and more dense, and in the process turns it into the very compact object that is a black hole. Then it reaches the maximal density and also a core of minimum size. At that point it starts to expand back, its as if you were seeing a movie in rewind, and everything starts expanding in the form of an explosion. If you can have things exploding back, this can also provide a possible window to search for quantum gravity, and we can look for traces of such an explosion.
So how does loop quantum gravity theory allow for the computation of the black hole lifetime?
The kind of computation that we are doing in quantum mechanics involves computing probabilities to go from one state to another. At this stage, we are configuring states of the geometry itself, so we have a state that corresponds to classical geometry. Take for example the classical geometry of a black hole. In other states, that corresponds to another classical geometry, which is the classical description of the white hole. The two states are, basically, exactly the same except for a flip of the curvature, one the inverse of the other with respect to the curvature.
In loop quantum gravity, we can write down the transition amplitudes, i.e. probabilities to go from one state to the other. While this is a quantum process, it can be connected to the time measured by an external observer for this process to happen. This research is something that is ongoing, so what is nice is that we have a theory to write down, concretely, these probabilities. Computing these discretions, these integrals, is complicated. One possibility is to try to solve these equations numerically, which is something we are doing now.
At this time, its not clear if we can have a transition to a white hole when the black hole is macroscopicvery big. But the probability becomes very high when the black hole is smaller, as in the case of a black hole that has undergone the Hawking evaporation and become very small. In that case, you really have a situation where the probability for this black hole to become a white hole is just one. Its unavoidable. Its possible you may end up having a very small compact object of Planck size that is in a superposition. They are black and white at the same time because they behave like quantum objectsso they can be in two states at the same time.
So this will be a manifestation of what it means for space-time to be quantized. In the quantum theory, superposition is one of the main features. For quantum gravity, being in a superposition means being in the superposition of different geometries. Here, I was giving you an example where you can really have a proposition of two different geometries, a black and a white geometry, together and in the same object.
How much influence do you think that different epistemologies have on our current understanding of theoretical physics?
Philosophy has always had a strong influence in the way in which we do physics. This was true for all of the great moments in physics. Both general relativity and quantum mechanics were born in a fertile philosophical environment, influenced for instance by the philosophy of Mach, or the philosophy of Poincar. Einstein was even influenced by Schopenhauer. Those philosophers urged us to look at a world beyond the physics given by Newtonian mechanics. The twentieth century revolutions in physics were really inspired and fueled by philosophers.
Sometimes people dont have a clear idea of what philosophy means. They have some romantic idea that philosophy is about the meaning of life, something like that. Instead, philosophy is a set of tools. The same way in which physics is a set of tools to think about the world using the language of mathematics, philosophy is also a sharp set of tools to distinguish clearly what the premises are of our way of thinking. Its like a cleaning method for thinking.
I think that there is no physicist who does physics without being guided by some kind of philosophy. What I mean is that you should have a picture of what youre doing, what your methods are, what your goal is, and what you want to understand. Without a clear philosophy, you risk doing bad physics. All the great physicists, of the past and of the present, had very good training in philosophy.
Can you share the philosophy that guides your own work within theoretical physics?
My way of professing in physics is not about the unification of forces, but I do have a drive towards looking for a common language, something that provides consistent features for all the different things that we have learned in fundamental physics. For me, what is more striking is how there is a form of relationality that emerges in all the different fields of contemporary physics. From quantum mechanics to general relativity to quantum field theory to quantum gravity, we understand better and better that all of the properties that we describe for physical systems always have to be related to something else. You can think about this something else as an observer or a reference system.
We always have to specify with respect to which system we are describing a given property, even things that are supposed to be at the foundation of our understanding of the world, like things. What do we call a thing? Do we call a thing a particle? Even the answer to questions about how many particles there are, how many particles a device detects, depends on the respective system we give this property. Then you start realizing that instead of thinking about the world in terms of things, its better to think about the world in terms of relations.
My philosophical background was also informed by the feminist philosophy of sciences. Feminist philosophers have been debating how you can have a notion of objectivity while there are so many different standpoints. From each standpoint, you have access to a bit of truth, but if you want to have a full description of reality, somehow again you have to accept this plurality of standpoints and eventually find a way to put them together. I believe this gives you a powerful key to interpret the world in which we live.
In the moment in which you confront yourself with what the new physics is telling you, there are two possible ways to react to this as a physicist. You can reject what nature is telling you, hanging on to some very rigid notion of truth and objectivity; or you may embrace it and try to look for the consequences of it. For me, embracing this second possibility is much more easy, and I see this as a very rich and fruitful way of thinking.
* * *
Loop quantum gravity: A candidate theory of quantum gravity that focuses on loops or discrete chunks organizing the geometry of quantum spacetime.
Path integral: Path integral formulation, devised by American physicist Richard P. Feynman, is a mathematical theory for understanding all the possible paths a quantum particle can take to get from one point to another.
Primordial quantum fluctuations: The initial conditions that seeded the universe and everything in it, including the galaxies, planets, and stars.
Quantum gravity: A theory, still in progress, explaining how gravity works on the quantum scale. A universally accepted theory of quantum gravity could bridge the gap between quantum physics and general relativity.
Spin foam: A 2-dimensional model with labeled edges, vertices, and faces with the goal of describing the geometry of quantum spacetime.
White hole: White holes are theoretical opposites of black holes. They spit out matter and energy, as opposed to consuming everything.
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Francesca Vidotto: The Quantum Properties of Space-Time - JSTOR Daily
David Baddiel: Kids have a better sense of humour than they used to’ – The Guardian
L
ike many, I began lockdown by bingeing on Tiger King, which remains one of the most extraordinary pieces of TV Ive ever seen although Ive become disenchanted with the, ahem, lionisation of it since, particularly the reflexive mass-hatred of the only significant woman in it. Nonetheless, its a hilariously disturbing portrait of just how wrong a self-enclosed world can go.
I havent watched many films. I saw Once Upon a Time in Hollywood, which felt from another era. By which I mean, not the 1960s but from when it was made, pre-coronavirus Tarantinos retro worldview may now itself be retro. I also watched the extraordinary 2015 documentary about North Korea, Under the Sun, by the Russian film-maker Vitaly Mansky [now on Amazon Prime Video]. The films power comes from simply letting the camera run between scenes, thus showing the way the state handlers cack-handedly try and manufacture those scenes. It is intensely slow, but hilarious and heartbreaking.
I liked the BBC Two series Devs. Gods Dice, a play I wrote that was on in London last autumn, was born out of a sense of the miraculousness of quantum physics and its strange relationship to religion, and Devs touches on much of the same material. As someone obsessed in an extremely lay way with quantum physics, I was impressed by how much science Alex Garland managed to fit around the drama. Im a sucker for a corporate tech thriller that can throw in and not just in a just make it sound impressive way many-worlds interpretation and the double-slit experiment.
But the big winner in our house has been Bojack Horseman. Weve always been animation fans Morwenna [Banks, Baddiels wife] is, of course, the voice of Mummy Pig in Peppa Pig and one of the reasons I write kids books is that kids have much better senses of humour than they used to: a generation of children raised on The Simpsons and The Amazing World of Gumball can now appreciate proper funny at a much earlier age than those who were reared on The Magic Roundabout. But Bojack isnt for kids (although I was introduced to it by my teenage son). Its a meticulously written, at once cynical and heartfelt, long-form comic saga about the emptiness of fame and the impossibility of connection in a world of surfaces, all channelled through a horse who was a big sitcom star in the 90s. It confirms something Ive thought for a very long time, which is that the greatest expression of TV and film as an art form is now happening in animation. Which, given that live-action actors are going to find it hard interacting on camera in the foreseeable future, may be no bad thing.
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David Baddiel: Kids have a better sense of humour than they used to' - The Guardian
MIT Student Probing Reality Through Physics, Philosophy and Writing – SciTechDaily
During the Independent Activities Period in 2018, senior Michelle Xu worked with the volunteer group Cross Cultural Solutions at the Ritsona refugee camp in Greece, through the Priscilla King Gray Public Service Center. I may not make a career out of public service, but I am a human being, and just like any other human being, helping the world is important to me, Xu explains. Credit: Ian MacLellan
MIT Senior Michelle Xus varied interests all involve a desire to understand the universe. I was just never particularly picky about which way to figure it out, she says.
A day in the life of Michelle Xu might include attending a quantum gravity seminar over Zoom, followed by some reading on the philosophy of time, capped off by a couple of hours of writing fiction.
If these activities seem wildly diverse, for Xu they all emerge from the same place: this desire to understand how the universe works, she says. I was just never particularly picky about which way to figure it out.
Xu is a senior majoring in physics and mathematics, with an added focus on philosophy. Her studies have centered on large questions in cosmology, including looking at the earliest days of the expanding universe through their impact on primordial black holes with Professor Alan Guth in the MIT Center for Theoretical Physics. Lately Xu has been studying high energy theory and quantum gravity under the guidance of Professor Daniel Harlow, both topics which she hopes to continue studying in graduate school at Stanford University next fall. Throughout her time in the physics department, professors Robert Jaffe, Tracy Slatyer, and David Kaiser have been strong role models and mentors as well, she says. My path in physics has been shaped and encouraged by all of these people, and without them, I wouldnt be where I am today.
During the Independent Activities Period in 2018, senior Michelle Xu worked with the volunteer group Cross Cultural Solutions at the Ritsona refugee camp in Greece, through the Priscilla King Gray Public Service Center. I may not make a career out of public service, but I am a human being, and just like any other human being, helping the world is important to me, Xu explains. Credit: Ian MacLellan
Although she was interested in physics when she first came to MIT, it was the research experience that confirmed for her that she was on the right career path. My biggest doubt was, OK, so I can do [problem sets], and I enjoy thinking about these concepts, but if I were tossed a bunch of equations and had to create something myself, could I actually do this? Xu recalls. Each summer as I worked on a different research project, I became more and more convinced that this was something I could do.
At home in Pennsylvania during the coronavirus pandemic, Xu is continuing her research with Guth and hopes to meet virtually with Harlow as well. She is staying touch with friends through social media, even starting a book club while they are scattered throughout the country. Ive been stripped of some of my usual responsibilities, like running clubs, so Im focusing more on personal interests like writing and some puzzling topics in physics and philosophy, she says.
Xus parents are scientists, and she was raised in a household where everything was approached from a scientific perspective, she says. They watched a lot of science documentaries, like Brian Greenes The Elegant Universe, that raised early questions about the nature of reality.
It was the class 24.02 (Moral Problems and the Good Life) that inspired Xu to delve deeper into philosophy as another way to probe reality. She later discovered that most of her philosophical interests lie in metaphysics and not ethics, but the problems were nevertheless interesting enough to get her hooked initially. She recalls one class discussion centered around morality and meaning in ones life, in relation to ideas like motivation and duty, that sparked an intense discussion with the classs teaching assistant. I got nerd sniped, Xu jokes. When someone poses such an interesting question or argument, you have to just drop everything to reply to it.
The TA invited her to sit in on a graduate philosophy reading group, and Xu also joined the MIT Undergraduate Philosophy Club and became a member of its executive board. She spent the spring 2019 semester at Oxford University studying philosophy and physics and in the summer participated in a weeklong summer school on mathematical philosophy for female students at Ludwig Maximilian University.
The jargon of academic philosophy can be as dense as physics terminology, Xu admits, but I think everyone could use a little philosophy in their lives. I think questions about life and the world around us can be structured in fascinating ways through the different modes of thinking in philosophy.
Thoughts about morality and responsibility came into focus for Xu during the Independent Activities Period in 2018, when she worked with the volunteer group Cross Cultural Solutions at the Ritsona refugee camp in Greece, through the Priscilla King Gray Public Service Center. People have asked her how the volunteer work fits in with her other academic interests, and she says the short answer is that it doesnt.
I may not make a career out of public service, but I am a human being, and just like any other human being, helping the world is important to me, Xu explains. Out there, I can do what any human can do do laundry or distribute food, and help people through an incredibly difficult time of their lives.
Xu shared her experiences at the refugee camp in writing, another long-time interest of hers. Inspired by the interdisciplinary science magazine Nautilus and looking for writing partners, Xu founded Chroma, MITs student-run science and humanities magazine. As editor-in-chief, she has been proud to encourage new writers, artists, and designers on campus to cross-pollinate ideas.
I think MIT is one of the few places where something like this can blossom, because everyone here is interested in the sciences in some way, she says.
Xu mostly writes fiction these days, which she calls variably OK, but hopefully improving. Last fall she took the class 21W.755 (Writing and Reading Short Stories) to sharpen her skills, because I have these things that I want to express in my writing but feel like I lack the technique to do. But especially now that Im quarantined, Im trying to write more just getting the reps in.
Writing also helps her grapple with the nature of reality in a different way, she says. To write is to build another reality. And to build something, you have to understand it.
Despite her consistent interest in the fundamental nature of reality, Xu says she does sometimes worry that perhaps she is spread across too many departments. If I want to do something significant and contribute to this world, does that mean I am lacking focus to do that correctly?
But I think you have to stay true to doing the things that pull you in, and thats the only way you can make a significant contribution to the world.
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MIT Student Probing Reality Through Physics, Philosophy and Writing - SciTechDaily
This is the light they have discovered and according to scientists it should not exist – Checkersaga
The field of quantum computing is one of those that still hold the most unknowns for scientists and where the news that continues to sometimes revolutionize previous theses or to rethink everything that has been known so far continues to spread. One of the latter is especially striking, the discovery of a light that according to scientists should not exist.
The discovery of baptized as forbidden light It has come from a group of scientists from Iowa State University (USA) and has been detected by light waves at high frequencies They have been used to accelerate superconductors of electric current and to study quantum physics.
When conducting the study published in Physical Review Letters, according to the BBC, they found second harmonic light emissions, something that was considered impossible until now.
Based on the existing knowledge of quantum physics, the scientist involved in the study Jigang Wang states that These second harmonic terahertz emissions are prohibited in superconductors (by the laws of physics). This goes against conventional wisdom
This discovery not only changes everything that was known about quantum matter, but also opens the door to study new phenomena and possibilities that were considered discarded and unthinkable previously. Starting with the most practical in the short term, creating quantum computers with even more speed.
Now opens a period where they will study this discovery in detail. It will be tested by more scientists and in other circumstances to observe the reliability and possibilities that exist, but in the first place, it seems that this impossible light may be a milestone.
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This is the light they have discovered and according to scientists it should not exist - Checkersaga
Looking up: UFO occupants and the legacy of language – Roswell Daily Record
By Donald Burleson
Special to the Daily
Record
Reportedly, we have had some exposure to the languages used by UFO crews. Some primary witnesses described peculiar inscriptions seen on the 1947 Roswell wreckage, and when physicist Robert Oppenheimer was present at the 1948 Aztec, New Mexico, UFO crash retrieval as part of the scientific team summoned to examine the craft, he took notice of alien markings adorning a sort of book found inside, observing that the inscriptions rather resembled Sanskrit, a classical language with which he was familiar.
One wishes we could know more about these strange symbols strange to us, anyway in terms of the eternal mysteries of language.
In the study of linguistics, theres a theory called the Sapir-Whorf Hypothesis, which essentially says that the structure of the language a person learns to speak in childhood largely determines the way that person perceives and categorizes the world. Different languages impart different world-views.
For example, in the world of scientists, there may be linguistic factors relating to the fact that speakers of Asian languages often excel at quantum mechanics.
For western scientists, quantum theory is frequently experienced as counter-intuitive. Its basic precepts seem to run contrary to common sense. Take particle entanglement, for instance. We entangle two particles, project them in opposite directions at the speed of light, alter the spin of one of the departing particles, and the spin of the other particle is instantly altered, as well. Some scientists initially found this so unreasonable that they refused to believe it until they saw experiments proving it true.
The reason for this reaction, in keeping with the Sapir-Whorf Hypothesis, may be that in western countries, we speak languages in which the relation between nouns and verbs would encourage us to think of particles as things rather than processes. But in quantum physics, one needs to think of a subatomic particle not as a thing but as a spectrum of events. Asian languages tend to favor this way of seeing the world from the outset, so that in effect, the speakers of such languages experience a fairly natural affinity with quantum theory.
We may only speculate, of course, on how the users of those peculiar-looking UFO inscriptions are prompted to see the universe, due to the nature of their languages. What if those languages revolve around grammatical structures so friendly to quantum concepts that they give their speakers an even more dramatic scientific advantage than that which is arguably enjoyed by speakers of some languages here on Earth? Its entirely possible that an alien languages form conduces to giving its speakers, at an early age, profound insights into the most arcane aspects of science. After all, UFOs exhibit an undeniably advanced technology.
And if, as many speculate, some UFOs are time travelers from our own distant future, things get more intriguing still. We know how our own languages have evolved over the past few thousand years, but what about the next million years? Maybe linguistically were in the slow process of becoming better scientists all the time.
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Looking up: UFO occupants and the legacy of language - Roswell Daily Record