Showing posts with label quantum mechanics. Show all posts
Showing posts with label quantum mechanics. Show all posts

Wednesday, May 1

Atoms Morph into Quantum Waves


In the 1920s, the pioneering physicist Erwin Schrödinger formulated an equation that fundamentally transformed our understanding of the universe. Schrödinger's equation describes how particles can behave like waves, a concept that underpins much of quantum mechanics. 

Now, nearly a century later, researchers have made a remarkable advancement that perfectly recreates Schrödinger's predictions in the laboratory: capturing single atoms morphing into quantum waves.

A Historic Moment in Quantum Imaging
The recent breakthrough involves capturing images of individual atoms exhibiting wave-like behavior. This is a historic achievement, as it provides the clearest image ever seen of atoms behaving like quantum waves, just as predicted by Schrödinger's equation. 

This discovery opens up exciting possibilities for studying and understanding the exotic and often mysterious behavior of atoms at the quantum level.  READ MORE...

Sunday, December 10

Theory Unites Gravity and Quantum Mechanics


A radical theory that consistently unifies gravity and quantum mechanics while preserving Einstein's classical concept of spacetime has been announced in two papers published simultaneously by UCL (University College London) physicists.

Modern physics is founded upon two pillars: quantum theory on the one hand, which governs the smallest particles in the universe, and Einstein's theory of general relativity on the other, which explains gravity through the bending of spacetime. But these two theories are in contradiction with each other and a reconciliation has remained elusive for over a century.

The prevailing assumption has been that Einstein's theory of gravity must be modified, or "quantized," in order to fit within quantum theory. This is the approach of two leading candidates for a quantum theory of gravity, string theory and loop quantum gravity.   READ MORE...

Friday, July 14

Time Reversal

A team of researchers from the University of Twente has successfully illustrated that quantum mechanics and thermodynamics can coexist by using an optical chip with photon channels. The channels individually showed disorder in line with thermodynamics, while the overall system complied with quantum mechanics due to the entanglement of subsystems, proving that information can be preserved and transferred. Credit: University of Twente




It seems quantum mechanics and thermodynamics cannot be true simultaneously. In a new publication, University of Twente researchers use photons in an optical chip to demonstrate how both theories can be true at the same time.

In quantum mechanics, time can be reversed and information is always preserved. That is, one can always find back the previous state of particles. It was long unknown how this could be true at the same time as thermodynamics. 

There, time has a direction and information can also be lost. “Just think of two photographs that you put in the sun for too long, after a while you can no longer distinguish them,” explains author Jelmer Renema.

There was already a theoretical solution to this quantum puzzle and even an experiment with atoms, but now the University of Twente (UT) researchers have also demonstrated it with photons. “Photons have the advantage that it is quite easy to reverse time with them,” explains Renema. 

In the experiment, the researchers used an optical chip with channels through which the photons could pass. At first, they could determine exactly how many photons there were in each channel, but after that, the photons shuffled positions.  READ MORE...

Tuesday, February 7

Quantum Entanglement: Spacetime is an illusion


This past December, the physics Nobel Prize was awarded for the experimental confirmation of a quantum phenomenon known for more than 80 years: entanglement. As envisioned by Albert Einstein and his collaborators in 1935, quantum objects can be mysteriously correlated even if they are separated by large distances. But as weird as the phenomenon appears, why is such an old idea still worth the most prestigious prize in physics?

Coincidentally, just a few weeks before the new Nobel laureates were honored in Stockholm, a different team of distinguished scientists from Harvard, MIT, Caltech, Fermilab and Google reported that they had run a process on Google’s quantum computer that could be interpreted as a wormhole. Wormholes are tunnels through the universe that can work like a shortcut through space and time and are loved by science fiction fans, and although the tunnel realized in this recent experiment exists only in a 2-dimensional toy universe, it could constitute a breakthrough for future research at the forefront of physics.

But why is entanglement related to space and time? And how can it be important for future physics breakthroughs? Properly understood, entanglement implies that the universe is “monistic”, as philosophers call it, that on the most fundamental level, everything in the universe is part of a single, unified whole. It is a defining property of quantum mechanics that its underlying reality is described in terms of waves, and a monistic universe would require a universal function. 

Already decades ago, researchers such as Hugh Everett and Dieter Zeh showed how our daily-life reality can emerge out of such a universal quantum-mechanical description. But only now are researchers such as Leonard Susskind or Sean Carroll developing ideas on how this hidden quantum reality might explain not only matter but also the fabric of space and time.

Entanglement is much more than just another weird quantum phenomenon. It is the acting principle behind both why quantum mechanics merges the world into one and why we experience this fundamental unity as many separate objects. At the same time, entanglement is the reason why we seem to live in a classical reality. It is—quite literally—the glue and creator of worlds. 

Entanglement applies to objects comprising two or more components and describes what happens when the quantum principle that “everything that can happen actually happens” is applied to such composed objects. Accordingly, an entangled state is the superposition of all possible combinations that the components of a composed object can be in to produce the same overall result. It is again the wavy nature of the quantum domain that can help to illustrate how entanglement actually works.

Picture a perfectly calm, glassy sea on a windless day. Now ask yourself, how can such a plane be produced by overlaying two individual wave patterns? One possibility is that superimposing two completely flat surfaces results again in a completely level outcome. But another possibility that might produce a flat surface is if two identical wave patterns shifted by half an oscillation cycle were to be superimposed on one another, so that the wave crests of one pattern annihilate the wave troughs of the other one and vice versa. If we just observed the glassy ocean, regarding it as the result of two swells combined, there would be no way for us to find out about the patterns of the individual swells. 

What sounds perfectly ordinary when we talk about waves has the most bizarre consequences when applied to competing realities. If your neighbor told you she had two cats, one live cat and a dead one, this would imply that either the first cat or the second one is dead and that the remaining cat, respectively, is alive—it would be a strange and morbid way of describing one’s pets, and you may not know which one of them is the lucky one, but you would get the neighbor’s drift. Not so in the quantum world. 

In quantum mechanics, the very same statement implies that the two cats are merged in a superposition of cases, including the first cat being alive and the second one dead and the first cat being dead while the second one lives, but also possibilities where both cats are half alive and half dead, or the first cat is one-third alive, while the second feline adds the missing two-thirds of life. In a quantum pair of cats, the fates and conditions of the individual animals get dissolved entirely in the state of the whole. Likewise, in a quantum universe, there are no individual objects. All that exists is merged into a single “One.”  READ MORE...

Tuesday, May 3

Time Does Not Exist (?)


Does time exist? The answer to this question may seem obvious: Of course it does! Just look at a calendar or a clock.

But developments in physics suggest the non-existence of time is an open possibility, and one that we should take seriously.

How can that be, and what would it mean? It'll take a little while to explain, but don't worry: Even if time doesn't exist, our lives will go on as usual.

A crisis in physics
Physics is in crisis. For the past century or so, we have explained the Universe with two wildly successful physical theories: general relativity and quantum mechanics.

Quantum mechanics describes how things work in the incredibly tiny world of particles and particle interactions. General relativity describes the big picture of gravity and how objects move.

Both theories work extremely well in their own right, but the two are thought to conflict with one another. Though the exact nature of the conflict is controversial, scientists generally agree both theories need to be replaced with a new, more general theory.

Physicists want to produce a theory of "quantum gravity" that replaces general relativity and quantum mechanics, while capturing the extraordinary success of both. Such a theory would explain how gravity's big picture works at the miniature scale of particles.

Time in quantum gravity
It turns out that producing a theory of quantum gravity is extraordinarily difficult.

One attempt to overcome the conflict between the two theories is string theory. String theory replaces particles with strings vibrating in as many as 11 dimensions.  READ MORE...

Thursday, April 21

Weirdness of Quantum Mechanics


Quantum mechanics has a way of taking your mind to places it just doesn’t want to go. Famously hard to understand and impossible to intuit, concepts such as quantum entanglement and superposition really make sense only when viewed through a mathematical lens. Plain language most often leads you down dead ends or false paths that end miles away from reality, with carelessly chosen words propagating misunderstandings at the speed of the internet.

A well-known case in point comes from Albert Einstein. The baked-in weirdness of quantum mechanics troubled him, leading to two celebrated quotes. One— “God does not play dice with the universe”—expressed his unease about the reign of probability over certainty in the quantum realm.

In the other quote, Einstein challenged the notion of the probabilistic correlations among particles, known as quantum entanglement, saying, “I cannot seriously believe in it because the theory cannot be reconciled with the idea that physics should represent a reality in time and space, free from spooky action at a distance.”

That last phrase has launched a thousand misguided speculations about faster-than-light communications. The main problem lies in the word action. It leans toward cause and effect—something directly affecting something else—and implies an unknown mechanism instantaneously operating on widely separated particles. 

That influence would clearly violate both the locality principle in physics (objects are only influenced by what’s nearby) and Einstein’s own Special Theory of Relativity, which set the universal speed limit at the speed of light, a theory backed up by observational evidence for a hundred years.

Entanglement refers to the condition of a system composed of atomic-scale particles whose states cannot be fully described independently or individually. John Preskill of Caltech described the situation with a literary metaphor. Someone who read 10 pages of a 100-page book composed in the classical, or non-quantum, physics world, would learn 10% of the book. 

Reading 10 pages of a quantum book would reveal almost nothing about the book’s contents. As Preskill says, “nearly all the information in the book is encoded in the correlations among the pages.” This principle of quantum mechanics has practical application as the basis for the power of quantum computing and other technologies because you can store information globally within the quantum system.  READ MORE...

Wednesday, March 16

Quantum Mechanics and Free Will


Credit: francescoch/Getty Images

A conjecture called superdeterminism, outlined decades ago, is a response to several peculiarities of quantum mechanics: the apparent randomness of quantum events; their apparent dependence on human observation, or measurement; and the apparent ability of a measurement in one place to determine, instantly, the outcome of a measurement elsewhere, an effect called nonlocality.

Einstein, who derided nonlocality as “spooky action at a distance,” insisted that quantum mechanics must be incomplete; there must be hidden variables that the theory overlooks. Superdeterminism is a radical hidden-variables theory proposed by physicist John Bell. He is renowned for a 1964 theorem, now named after him, that dramatically exposes the nonlocality of quantum mechanics.

Bell said in a BBC interview in 1985 that the puzzle of nonlocality vanishes if you assume that “the world is superdeterministic, with not just inanimate nature running on behind-the-scenes clockwork, but with our behavior, including our belief that we are free to choose to do one experiment rather than another, absolutely predetermined.”

In a recent video, physicist Sabine Hossenfelder, whose work I admire, notes that superdeterminism eliminates the apparent randomness of quantum mechanics. “In quantum mechanics,” she explains, “we can only predict probabilities for measurement outcomes, rather than the measurement outcomes themselves. The outcomes are not determined, so quantum mechanics is indeterministic. Superdeterminism returns us to determinism.”

“The reason we can’t predict the outcome of a quantum measurement,” she explains, “is that we are missing information,” that is, hidden variables. Superdeterminism, she notes, gets rid of the measurement problem and nonlocality as well as randomness. Hidden variables determine in advance how physicists carry out the experiments; physicists might think they are choosing one option over another, but they aren’t. Hossenfelder calls free will “logically incoherent nonsense.”

Hossenfelder predicts that physicists might be able to confirm superdeterminism experimentally. “At some point,” she says, “it’ll just become obvious that measurement outcomes are actually much more predictable than quantum mechanics says. Indeed, maybe someone already has the data, they just haven’t analyzed it the right way.” Hossenfelder defends superdeterminism in more detail in a technical paper written with physicist Tim Palmer.  

AUTHOR  -  John Horgan directs the Center for Science Writings at the Stevens Institute of Technology. His books include The End of Science, The End of War and Mind-Body Problems, available for free at mindbodyproblems.com. For many years he wrote the popular blog Cross Check for Scientific American.


TO READ MORE, CLICK HERE...


Sunday, August 29

Metaphysical Mysteries


In my 20s, I had a friend who was brilliant, charming, Ivy-educated and rich, heir to a family fortune. I’ll call him Gallagher. He could do anything he wanted. He experimented, dabbling in neuroscience, law, philosophy and other fields. 

But he was so critical, so picky, that he never settled on a career. Nothing was good enough for him. He never found love for the same reason. He also disparaged his friends’ choices, so much so that he alienated us. He ended up bitter and alone. At least that’s my guess. I haven’t spoken to Gallagher in decades.

There is such a thing as being too picky, especially when it comes to things like work, love and nourishment (even the pickiest eater has to eat something). That’s the lesson I gleaned from Gallagher. But when it comes to answers to big mysteries, most of us aren’t picky enough. 

We settle on answers for bad reasons, for example, because our parents, priests or professors believe it. We think we need to believe something, but actually we don’t. We can, and should, decide that no answers are good enough. We should be agnostics.

Some people confuse agnosticism (not knowing) with apathy (not caring). Take Francis Collins, a geneticist who directs the National Institutes of Health. He is a devout Christian, who believes that Jesus performed miracles, died for our sins and rose from the dead. In his 2006 bestseller The Language of God

Collins calls agnosticism a “cop-out.” When I interviewed him, I told him I am an agnostic and objected to “cop-out.”  READ MORE

Thursday, August 5

What is Life

In 1943, one of the fathers of quantum mechanics, famous for his equation and his cat, Erwin Schrödinger, turned his attention to a problem that was seemingly simple but defied an easy answer. As World War 2 raged, he published a book titled What is Life?

Based on a series of lectures given in Dublin, the book’s theme was to answer the question: “how can the events in space and time which take place within the spatial boundary of a living organism be accounted for by physics and chemistry?”

In other words: What is Life? Or, from a physicist’s point of view, how can life arise from inanimate matter.

Much of the lecture discussed the requirement for genetic material and some sort of encoding as well as how life related to thermodynamics — the laws governing energy, heat transport, and disorder.

Although their success largely depended on Rosalind Franklin’s X-ray diffraction experiments, Francis and Crick would also credit Schrödinger’s work for inspiring their research resulting in the discovery of the DNA double helix.

Schrödinger’s primary insight is that life creates order from disorder. In a universe governed by the 2nd law of thermodynamics, that all things tend to maximal disorder, living things maintain small enclaves of order within themselves. Moreover, if you look down to the atomic level, you find that the interiors of living things are extremely chaotic. Heat and molecules diffuse through rapid motion. Everything seems random. Yet the living thing persists, turning all that small scale chaos into large scale order.

Human built machines, by contrast, attempt to maintain order down to the smallest relevant levels. Microchips, for example, depend on orderly transfer of data down to nanometers. Precision machine tools, likewise, function because they have an exact specification at nearly the molecular level. The result is that human tools require careful protection and maintenance and break easily when subjected to the elements.

Life, on the other hand, has withstood the elements for billions of years precisely because it is able to build order out of chaos.  READ MORE

Monday, July 26

Consciousness and Quantum Physics

One of the most important open questions in science is how our consciousness is established. In the 1990s, long before winning the 2020 Nobel Prize in Physics for his prediction of black holes, physicist Roger Penrose teamed up with anesthesiologist Stuart Hameroff to propose an ambitious answer.

They claimed that the brain's neuronal system forms an intricate network and that the consciousness this produces should obey the rules of quantum mechanics – the theory that determines how tiny particles like electrons move around. This, they argue, could explain the mysterious complexity of human consciousness.

Penrose and Hameroff were met with incredulity. Quantum mechanical laws are usually only found to apply at very low temperatures. Quantum computers, for example, currently operate at around -272°C. At higher temperatures, classical mechanics takes over.

Since our body works at room temperature, you would expect it to be governed by the classical laws of physics. For this reason, the quantum consciousness theory has been dismissed outright by many scientists – though others are persuaded supportersREAD MORE

Wednesday, June 2

the Quantum Revolution



As you read these words the world around you seems pretty solid, pretty stable: The device you're using seems to exist on its own, with its own properties of shape and weight and color. So does the chair you're sitting in, the table your coffee cup is resting on and the coffee cup itself.

But that solidity and independence is a kind illusion or, at least, so says the very physics that lets these words appear on the screen of your computer, smart phone or tablet.

That physics, called quantum mechanics, represents the most powerful theory human beings have ever developed. And while we scientists know how to use it to make all those digital devices, we do not know what it means. We don't know what it's telling us about the fundamental nature of reality. It is into that chasm that acclaimed theoretical physicist and author Carlo Rovelli leaps with his new book Helgoland. Making Sense of the Quantum Revolution.

It's a leap you will want to take with him.

Quantum mechanics is now more than 100 years old. It was born at the turn of the 20th century as physicists probed the atomic and subatomic realms. Much to their chagrin, reality turned out to be a lot weirder at those scales than in the "classical" realm of ordinary experience. The theory they developed to control the objects of their experiments was an intellectual triumph. Almost all of the technological miracles we live with now — from CAT scans to computers — can be traced to that achievement. But quantum mechanics never really "explained" the strangeness of the microworld. It just gave us a method for making incredibly accurate predictions and building stuff.  TO READ MORE, CLICK HERE...

Friday, May 21

Predetermination

Our fate is written in the stars, so the old stories go. It makes for thrilling drama, but it isn't the way the Universe works. But there's an interesting effect of quantum mechanics that might leave an opening for a starry fate, so a team of researchers decided to test the idea.

The idea stems from a subtle effect of quantum physics demonstrated by the Einstein-Podolsky-Rosen (EPR) experiment. One of the basic properties of quantum objects is that their behavior isn't predetermined. The statistical behavior of a quantum system is governed by the laws of quantum theory, but the specific outcome of a particular measurement is indefinite until it's actually performed. This behavior manifests itself in things such as particle-wave duality, where photons and electrons can sometimes behave like particles and sometimes like waves.

One of the more subtle effects related to this property is known as entanglement, when two quantum objects have some kind of connection that allows you to gain information about object A by only interacting with object B. As a basic example, suppose I took a pair of shoes and sent one shoe to my brother in Cleveland, and the other to my sister in Albuquerque. Knowing what a prankster I am, when my sister opens the package and finds a left shoe, she immediately knows her brother was sent the right one. The fact that shoes come in pairs means they are an "entangled" system.

The difference between shoes and quantum entanglement is that the shoes already had a destined outcome. When I mailed the shoes days earlier, the die was already cast. Even if I didn't know which shoe I sent to my brother and sister, I definitely sent one or the other, and there was always a particular shoe in each box. My sister couldn't have opened the box to find a slipper. 

But with quantum entanglement, slippers are possible. In the quantum world, it would be like mailing the boxes where all I know is that they form a pair. It could be shoes, gloves or socks, and neither I nor my siblings would know what the boxes contain until one of them opens a box. But the moment my brother opens the box and finds a left-handed glove, he immediately knows our dear sister will be receiving its right-handed mate.  TO READ MORE, CLICK HERE...

Saturday, January 23

The Quantum Mind

The quantum mind or quantum consciousness is a group of hypotheses proposing that classical mechanics cannot explain consciousness. It posits that quantum-mechanical phenomena, such as entanglement and superposition, may play an important part in the brain's function and could explain consciousness.

Assertions that consciousness is somehow quantum-mechanical can overlap with quantum mysticism, a pseudoscientific movement that assigns supernatural characteristics to various quantum phenomena such as nonlocality and the observer effect.  

Eugene Wigner developed the idea that quantum mechanics has something to do with the workings of the mind. He proposed that the wave function collapses due to its interaction with consciousness. Freeman Dyson argued that "mind, as manifested by the capacity to make choices, is to some extent inherent in every electron.

Other contemporary The physicists and philosophers considered these arguments unconvincing. Victor Stenger characterized quantum consciousness as a "myth" having "no scientific basis" that "should take its place along with gods, unicorns and dragons."

David Chalmers argues against quantum consciousness. He instead discusses how quantum mechanics may relate to dualistic consciousness.  Chalmers is skeptical that any new physics can resolve the hard problem of consciousness.       
SOURCE:  Wikipedia


From Stanford University, we have this
:

The original motivation in the early 20th century for relating quantum theory to consciousness was essentially philosophical. It is fairly plausible that conscious free decisions (“free will”) are problematic in a perfectly deterministic world so quantum randomness might indeed open up novel possibilities for free will. (On the other hand, randomness is problematic for goal-directed volition!)


What is interesting here is the notion of the mind...   the consciousness...   the randomness of free will...  we use very little of our mind, so what is the rest of it there for?  

Why were we given something that we do not use?  

Why did we evolve something that we don't use because that is not how biological evolution works?

The quantum world is made of sub-sub-atomic energy strings that vibrate and move in unpredictable and random patterns which is why many theoretical physicists believe that there might be multiple dimensions.  However, when these strings are observed they move in a specific direction.

Why and How does this happen?

UNEXPLAINED...   just like the unused portion of the mind whose thoughts can be compared to the random movement of strings...  or perhaps, it is strings of the mind that causes the various episodes of our dreams...

Just the thought of this connection is mind boggling and overwhelming in its implications...


Monday, November 9

TIME: Past - Present - Future

Time is a commodity that is limited in its nature especially for all living things but time is also conceptualized with a PAST, PRESENT, and a FUTURE; although, we never see the past living in the present that always seems to lean more directly into the future...  since time moves forward not backward; and, we accept the past as what has been simply because we can read the records.  BUT, time is somewhat elusive in that we can never see what just happened and what just happened is never behind us even when we are walking backwards into our future...  so where did our immediate past go?

The breeze that blows by...  comes and goes but as it touches our bodies is all we know of its existence other than what we may observe but where it came from has disappeared into our past never to be seen again so we do not know for sure if the conditions that brought the breeze to us still there...  or perhaps the past goes into some kind of holding dimension.

Using telescopes we can see where space came from and where it is going but that ability stops as we observe the life we are living.  There will always be cars behind us on the interstate but we are all moving forward at the same relative time and even though we see a landscape behind us as we drive by, the conditions of that landscape are different than when we were just there...  just as every millisecond of our present is different so too is every millisecond of our past.

SO...  again...  where does our past go and that it goes so fast we cannot return?

A jet stream is a visual reminder and the actual past of a fast moving aircraft as it moves into its future pausing less than a nanosecond in its present; however, the physical aircraft's past is never seen as if it never been there in the first place yet we see its reminder as it floats behind eventually dissipating.    

Grave Stones are a reminder of someone's past but that is not exactly what I am talking about...  I want to know where our immediate past goes when we are still alive always moving into our future...  this is the question that bothers me and to which there is no easy reply and only speculative proof and our existence in our future that it actually happened at all or why we can never return.

Wednesday, April 1

A Quantum Reality

QUANTUM MECHANICS

Quantum Mechanics or QM, describes how the Universe works at the level smaller than atoms. It is also called "quantum physics" or "quantum theory". A quantum of energy is a specific amount of energy, and Quantum Mechanics describes how that energy moves and interacts at the sub-atomic level.


The new theory ignored the fact that electrons are particles and treated them as waves. By 1926 physicists had developed the laws of quantum mechanics, also called wave mechanics, to explain atomic and subatomic phenomena.  When X-rays are scattered, their momentum is partially transferred to the electrons.

The world as we know it has three dimensions of space—length, width and depth—and one dimension of time. But there's the mind-bending possibility that many more dimensions exist out there. According to string theory, one of the leading physics model of the last half century, the universe operates with 10 dimensions.


String theory is a set of attempts to model the four known fundamental interactions—gravitation, electromagnetism, strong nuclear force, weak nuclear force—together in one theory.  Einstein had sought a unified field theory, a single model to explain the fundamental interactions or mechanics of the universe.



One notable feature of string theories is that these theories require extra dimensions of spacetime for their mathematical consistency. In bosonic string theory, spacetime is 26-dimensional, while in superstring theory it is 10-dimensional, and in M-theory it is 11-dimensional.


M-theory is a new idea in small-particle physics that is part of superstring theory that was initially proposed by Edward Witten. The idea, or theory, often causes arguments among scientists, because there is no way to test it to see if it is true.


A type of spacetime symmetry, supersymmetry is a possible candidate for undiscovered particle physics, and seen by some physicists as an elegant solution to many current problems in particle physics if confirmed correct, which could resolve various areas where current theories are believed to be incomplete.