Physics, Chemistry, and Mathematics

[Typhoon]

Requiem for a string: Charting the rise and fall of a theory of everything

String theory was supposed to explain all of [fundamental] physics. What went wrong?

This article, uncharacteristically, pulls no punches

Four years later, the Higgs was found. Supersymmetry was not. It’s now 15 years later, and there are still no signs of supersymmetry.

In fact, all the “easy” versions of supersymmetry have been ruled out, and many of the more complicated ones, too. The dearth of evidence has slaughtered so many members of the supersymmetric family that the whole idea is on very shaky ground, with physicists beginning to have conferences with titles like “Beyond Supersymmetry” and “Oh My God, I Think I Wasted My Career.”

stating the part that is not be be spoken out load.

One question that bugs me that I have never seen anyone talk about After decoherence is there recoherence? IE does the wave function come back from collapse ? And if so how long does it take? And if it doesn't, does that mean our understanding of "wave particle duality" is very different than what is imagined by Schrodinger's cat?

Decoherence explains why we do not observed QM effects at the large, everyday, scale.

https://www.youtube.com/watch?v=igsuIuI_HAQ

igsuIuI_HAQ

This is a different aspect of QM to making a measurement of a quantum system - the collapse of the wavefunction [or in my preferred understanding, the projection of the linear superposition of states onto one of its basis states].

Schrödinger's cat is probably the most misunderstood meme in popular culture.

[Doc]

Requiem for a string: Charting the rise and fall of a theory of everything

String theory was supposed to explain all of [fundamental] physics. What went wrong?

This article, uncharacteristically, pulls no punches

Four years later, the Higgs was found. Supersymmetry was not. It’s now 15 years later, and there are still no signs of supersymmetry.

In fact, all the “easy” versions of supersymmetry have been ruled out, and many of the more complicated ones, too. The dearth of evidence has slaughtered so many members of the supersymmetric family that the whole idea is on very shaky ground, with physicists beginning to have conferences with titles like “Beyond Supersymmetry” and “Oh My God, I Think I Wasted My Career.”

stating the part that is not be be spoken out load.

One question that bugs me that I have never seen anyone talk about After decoherence is there recoherence? IE does the wave function come back from collapse ? And if so how long does it take? And if it doesn't, does that mean our understanding of "wave particle duality" is very different than what is imagined by Schrodinger's cat?

Decoherence explains why we do not observed QM effects at the large, everyday, scale.

https://www.youtube.com/watch?v=igsuIuI_HAQ

igsuIuI_HAQ

This is a different aspect of QM to making a measurement of a quantum system - the collapse of the wavefunction [or in my preferred understanding, the projection of the linear superposition of states onto one of its basis states].

Schrödinger's cat is probably the most misunderstood meme in popular culture.

You are the only contemporary physicist, besides Laue, who sees that one cannot get around the assumption of reality, if only one is honest. Most of them simply do not see what sort of risky game they are playing with reality—reality as something independent of what is experimentally established. Their interpretation is, however, refuted most elegantly by your system of radioactive atom + amplifier + charge of gun powder + cat in a box, in which the psi-function of the system contains both the cat alive and blown to bits. Nobody really doubts that the presence or absence of the cat is something independent of the act of observation.[9]

That presumes the cat does not observe whether or not it is alive or dead.
As I remember Quantum decoherence has been observed in Bose-Einstein condensate in the act of decohering.

As to my question I think I am doing a bad job expressing it so let me write exactly how it was a came to the question.

Thought experiment: A double slit experiment is run. There is s detector on the slits to measure which slit the photon passed through. Which of course causes the Wave function to decohere. However instead of recording this on a screen a few feet away from the slits the imaginary screen is placed one light year away(Or some large distance away ) from the double slits. Which leads to my question: When the photon is detected far far away from the slits will it still be in a state of decoherence?

It seems to me that the sum of uncertainty of Heisenberg uncertainty principle over distance/time would determine the wave functions expansion. Or alternately, once decohered is there no going back?

This is the question I have never seen addressed. I have other nagging thoughts that depend on the answer to the question. But if I am "Not even wrong", please don't spare my feelings. ;p

[Typhoon]

Quanta Mag | How Our Reality May Be a Sum of All Possible Realities

Dumb title, good lay article.

Richard Feynman’s path integral is both ... it means.

A particle’s actual path through space can be understood as the sum of all its possible paths.

[Typhoon]

Requiem for a string: Charting the rise and fall of a theory of everything

String theory was supposed to explain all of [fundamental] physics. What went wrong?

This article, uncharacteristically, pulls no punches

Four years later, the Higgs was found. Supersymmetry was not. It’s now 15 years later, and there are still no signs of supersymmetry.

In fact, all the “easy” versions of supersymmetry have been ruled out, and many of the more complicated ones, too. The dearth of evidence has slaughtered so many members of the supersymmetric family that the whole idea is on very shaky ground, with physicists beginning to have conferences with titles like “Beyond Supersymmetry” and “Oh My God, I Think I Wasted My Career.”

stating the part that is not be be spoken out load.

One question that bugs me that I have never seen anyone talk about After decoherence is there recoherence? IE does the wave function come back from collapse ? And if so how long does it take? And if it doesn't, does that mean our understanding of "wave particle duality" is very different than what is imagined by Schrodinger's cat?

Decoherence explains why we do not observed QM effects at the large, everyday, scale.

https://www.youtube.com/watch?v=igsuIuI_HAQ

igsuIuI_HAQ

This is a different aspect of QM to making a measurement of a quantum system - the collapse of the wavefunction [or in my preferred understanding, the projection of the linear superposition of states onto one of its basis states].

Schrödinger's cat is probably the most misunderstood meme in popular culture.

You are the only contemporary physicist, besides Laue, who sees that one cannot get around the assumption of reality, if only one is honest. Most of them simply do not see what sort of risky game they are playing with reality—reality as something independent of what is experimentally established. Their interpretation is, however, refuted most elegantly by your system of radioactive atom + amplifier + charge of gun powder + cat in a box, in which the psi-function of the system contains both the cat alive and blown to bits. Nobody really doubts that the presence or absence of the cat is something independent of the act of observation.[9]

That presumes the cat does not observe whether or not it is alive or dead.
As I remember Quantum decoherence has been observed in Bose-Einstein condensate in the act of decohering.

Certainly.

Decoherence of prepared quantum states before the calculation is complete is the main challenge to building a quantum computer.

As to my question I think I am doing a bad job expressing it so let me write exactly how it was a came to the question.

Thought experiment: A double slit experiment is run. There is s detector on the slits to measure which slit the photon passed through. Which of course causes the Wave function to decohere.

. . . causes the wave function to collapse.

However instead of recording this on a screen a few feet away from the slits the imaginary screen is placed one light year away(Or some large distance away ) from the double slits. Which leads to my question: When the photon is detected far far away from the slits will it still be in a state of decoherence?]

, , , collapse.

Yes, you would still get a Gaussian distribution rather than an interference pattern.

It seems to me that the sum of uncertainty of Heisenberg uncertainty principle over distance/time would determine the wave functions expansion. Or alternately, once decohered is there no going back?

Dr. Hossenfelder addresses this in her video, every time a quantum particle interacts with its environment, there is a shift in its phase exp(i * theta) where theta is the phase angle [Like her, I prefer to thing about QM in Dirac's <bra| |ket> representation].

This is the question I have never seen addressed. I have other nagging thoughts that depend on the answer to the question. But if I am "Not even wrong", please don't spare my feelings. ;p

[Doc]

Requiem for a string: Charting the rise and fall of a theory of everything

String theory was supposed to explain all of [fundamental] physics. What went wrong?

This article, uncharacteristically, pulls no punches

Four years later, the Higgs was found. Supersymmetry was not. It’s now 15 years later, and there are still no signs of supersymmetry.

In fact, all the “easy” versions of supersymmetry have been ruled out, and many of the more complicated ones, too. The dearth of evidence has slaughtered so many members of the supersymmetric family that the whole idea is on very shaky ground, with physicists beginning to have conferences with titles like “Beyond Supersymmetry” and “Oh My God, I Think I Wasted My Career.”

stating the part that is not be be spoken out load.

One question that bugs me that I have never seen anyone talk about After decoherence is there recoherence? IE does the wave function come back from collapse ? And if so how long does it take? And if it doesn't, does that mean our understanding of "wave particle duality" is very different than what is imagined by Schrodinger's cat?

Decoherence explains why we do not observed QM effects at the large, everyday, scale.

https://www.youtube.com/watch?v=igsuIuI_HAQ

igsuIuI_HAQ

This is a different aspect of QM to making a measurement of a quantum system - the collapse of the wavefunction [or in my preferred understanding, the projection of the linear superposition of states onto one of its basis states].

Schrödinger's cat is probably the most misunderstood meme in popular culture.

You are the only contemporary physicist, besides Laue, who sees that one cannot get around the assumption of reality, if only one is honest. Most of them simply do not see what sort of risky game they are playing with reality—reality as something independent of what is experimentally established. Their interpretation is, however, refuted most elegantly by your system of radioactive atom + amplifier + charge of gun powder + cat in a box, in which the psi-function of the system contains both the cat alive and blown to bits. Nobody really doubts that the presence or absence of the cat is something independent of the act of observation.[9]

That presumes the cat does not observe whether or not it is alive or dead.
As I remember Quantum decoherence has been observed in Bose-Einstein condensate in the act of decohering.

Certainly.

Decoherence of prepared quantum states before the calculation is complete is the main challenge to building a quantum computer.

As to my question I think I am doing a bad job expressing it so let me write exactly how it was a came to the question.

Thought experiment: A double slit experiment is run. There is s detector on the slits to measure which slit the photon passed through. Which of course causes the Wave function to decohere.

. . . causes the wave function to collapse.

However instead of recording this on a screen a few feet away from the slits the imaginary screen is placed one light year away(Or some large distance away ) from the double slits. Which leads to my question: When the photon is detected far far away from the slits will it still be in a state of decoherence?]

, , , collapse.

Yes, you would still get a Gaussian distribution rather than an interference pattern.

It seems to me that the sum of uncertainty of Heisenberg uncertainty principle over distance/time would determine the wave functions expansion. Or alternately, once decohered is there no going back?

Dr. Hossenfelder addresses this in her video, every time a quantum particle interacts with its environment, there is a shift in its phase exp(i * theta) where theta is the phase angle [Like her, I prefer to thing about QM in Dirac's <bra| |ket> representation].

Thanks for the answer. My understanding has always been that that the wave function comes from the uncertainty of position vs momentum of the particles in question. Obeying something akin to the power distribution law. Granted that these particles are typically traveling close to the speed of light so special relativity may have to be factored in.

But I still don't know whether or not the wave function reappears at a future time as the uncertainty of its position and moment become less knowable. Also if the wave function collapses once it is "observed" then why does it not collapse when it hits the screen. That is certainty an observation. I am sure there is a good explanation for that but I have not found an explanation for that as well. Does the photo electric effect of a group of photons of a non collapsed until it hit the screen generate electrons in a specific place without interference?

This is the question I have never seen addressed. I have other nagging thoughts that depend on the answer to the question. But if I am "Not even wrong", please don't spare my feelings. ;p

[Heracleum Persicum]

.

The "secret" behind Iran's precision guided ballistic missiles
Fiber-Optic Gyroscope!
Circular error probability (CEP) of less than 10 meters

. . highly sensitive gyroscopes that turn Iran's missiles into a lethal weapon without the need for external guidance !

A process that started decades ago in Iran and finally found its end in small high-precision optical gyroscopes !

[Doc]

Requiem for a string: Charting the rise and fall of a theory of everything



This article, uncharacteristically, pulls no punches



stating the part that is not be be spoken out load.

One question that bugs me that I have never seen anyone talk about After decoherence is there recoherence? IE does the wave function come back from collapse ? And if so how long does it take? And if it doesn't, does that mean our understanding of "wave particle duality" is very different than what is imagined by Schrodinger's cat?

Decoherence explains why we do not observed QM effects at the large, everyday, scale.

https://www.youtube.com/watch?v=igsuIuI_HAQ

igsuIuI_HAQ

This is a different aspect of QM to making a measurement of a quantum system - the collapse of the wavefunction [or in my preferred understanding, the projection of the linear superposition of states onto one of its basis states].

Schrödinger's cat is probably the most misunderstood meme in popular culture.

You are the only contemporary physicist, besides Laue, who sees that one cannot get around the assumption of reality, if only one is honest. Most of them simply do not see what sort of risky game they are playing with reality—reality as something independent of what is experimentally established. Their interpretation is, however, refuted most elegantly by your system of radioactive atom + amplifier + charge of gun powder + cat in a box, in which the psi-function of the system contains both the cat alive and blown to bits. Nobody really doubts that the presence or absence of the cat is something independent of the act of observation.[9]

That presumes the cat does not observe whether or not it is alive or dead.
As I remember Quantum decoherence has been observed in Bose-Einstein condensate in the act of decohering.

Certainly.

Decoherence of prepared quantum states before the calculation is complete is the main challenge to building a quantum computer.

As to my question I think I am doing a bad job expressing it so let me write exactly how it was a came to the question.

Thought experiment: A double slit experiment is run. There is s detector on the slits to measure which slit the photon passed through. Which of course causes the Wave function to decohere.

. . . causes the wave function to collapse.

However instead of recording this on a screen a few feet away from the slits the imaginary screen is placed one light year away(Or some large distance away ) from the double slits. Which leads to my question: When the photon is detected far far away from the slits will it still be in a state of decoherence?]

, , , collapse.

Yes, you would still get a Gaussian distribution rather than an interference pattern.

It seems to me that the sum of uncertainty of Heisenberg uncertainty principle over distance/time would determine the wave functions expansion. Or alternately, once decohered is there no going back?

Dr. Hossenfelder addresses this in her video, every time a quantum particle interacts with its environment, there is a shift in its phase exp(i * theta) where theta is the phase angle [Like her, I prefer to thing about QM in Dirac's <bra| |ket> representation].

Thanks for the answer. My understanding has always been that that the wave function comes from the uncertainty of position vs momentum of the particles in question. Obeying something akin to the power distribution law. Granted that these particles are typically traveling close to the speed of light so special relativity may have to be factored in.

But I still don't know whether or not the wave function reappears at a future time as the uncertainty of its position and moment become less knowable. Also if the wave function collapses once it is "observed" then why does it not collapse when it hits the screen. That is certainty an observation. I am sure there is a good explanation for that but I have not found an explanation for that as well. Does the photo electric effect of a group of photons of a non collapsed until it hit the screen generate electrons in a specific place without interference?

This is the question I have never seen addressed. I have other nagging thoughts that depend on the answer to the question. But if I am "Not even wrong", please don't spare my feelings. ;p

ME: After the collapse of a quantum wave / particle does the wave ever reappear?
ChatGPT:

The collapse of a quantum wave function is a fundamental concept in quantum mechanics that describes the transition from a superposition of states to a single state. When a quantum wave function collapses, it means that a measurement has been made and the system has interacted with its environment, causing the wave function to "collapse" into a definite state.

After the collapse of a quantum wave function, the system will remain in the measured state and will not return to its original superposition of states. This is because the act of measurement irreversibly changes the system and its wave function.

However, it is important to note that in quantum mechanics, the behavior of particles and waves can be probabilistic and described by wave functions that evolve over time. So while the collapse of a wave function is a sudden and irreversible event, the evolution of a wave function over time can lead to new probabilities for different outcomes, which can be measured and collapsed again.

Me:
How long does it take for a collasped wave/particle function to have new probabilities?
ChatGPT:

The time it takes for a collapsed wave function to evolve and develop new probabilities depends on the specifics of the system being observed and the measurement process that is performed on it.

In general, the time it takes for a wave function to develop new probabilities can be determined by the system's natural time scale, which is related to its energy, mass, and other properties. For example, the time it takes for an electron to move from one energy level to another in an atom can be calculated based on the properties of the electron and the atom.

It is also important to note that the act of measuring a quantum system can disturb it, which can affect the evolution of its wave function and the development of new probabilities. This is known as the measurement problem in quantum mechanics and is a subject of ongoing research and debate in the field.

In summary, the time it takes for a collapsed wave function to develop new probabilities is dependent on the specifics of the system and the measurement process, and can range from fractions of a second to much longer periods of time.

Me:
How much longer periods of time?
ChatGPT:

The amount of time it takes for a collapsed wave function to develop new probabilities can vary widely depending on the specific system being observed and the measurement process. In some cases, the development of new probabilities can occur very quickly, within fractions of a second. In other cases, it may take much longer, ranging from minutes to hours or even longer.

For example, in some experiments with cold atoms, the wave function can take several seconds to develop new probabilities after a measurement is made. In contrast, in some experiments with superconducting qubits, the wave function can develop new probabilities within nanoseconds.

Ultimately, the time scale for the development of new probabilities is determined by the properties of the system being observed and the measurement process being used, and can vary widely from case to case.

[Doc]

Great Youtube channel on physics

https://www.youtube.com/watch?v=bAedYtUredI

bAedYtUredI

How Does Light Actually Work?

[Typhoon]

Physics World | Physicists demonstrate Young’s double-slit interference in time

[Doc]

Physics World | Physicists demonstrate Young’s double-slit interference in time

Interesting I have to think about what exactly it means a bit. The Semiconductor would indeed make an excellent data switch. 100 gigabit internet. 12.5 gigabit on a single frequency anyway. Another thing I read recently that there are now photon cameras that can detect individual photons for quantum applications.

Also I wonder if anyone has done the double slit experiment in a strong electromagnetic field?

[Typhoon]

=ttps://bigthink.com/starts-with-a-bang ... Here’s why

For decades, theorists have been cooking up "theories of everything" to explain our Universe. Are all of them completely off-track?

[Doc]

=ttps://bigthink.com/starts-with-a-bang ... Here’s why

For decades, theorists have been cooking up "theories of everything" to explain our Universe. Are all of them completely off-track?

I watched a video last night that blew me away. I learned more from it about quantum than most other ways I have tried

https://www.youtube.com/watch?v=NyfNxspBfsc

It strikes me that physics talks about 4, 10, 11, and 26 dimensions, but it occurs to me that there might just be a lot more of them, rather than multiverses. Maybe an infinite number.

[Heracleum Persicum]

I watched a video last night that blew me away. I learned more from it about quantum than most other ways I have tried

https://www.youtube.com/watch?v=NyfNxspBfsc

It strikes me that physics talks about 4, 10, 11, and 26 dimensions, but it occurs to me that there might just be a lot more of them, rather than multiverses. Maybe an infinite number.

Interesting , thanks for posting

[Parodite]

Another quantum charlatan selling "entangled" snake oil.

[Doc]

I watched a video last night that blew me away. I learned more from it about quantum than most other ways I have tried

https://www.youtube.com/watch?v=NyfNxspBfsc

It strikes me that physics talks about 4, 10, 11, and 26 dimensions, but it occurs to me that there might just be a lot more of them, rather than multiverses. Maybe an infinite number.

Interesting , thanks for posting

The part at the end about photosynthesis I thought was the most interesting

[Parodite]

What would we see at the speed of light?

[Typhoon]

"String theory lied to us and now science communication is hard".

https://www.youtube.com/watch?v=kya_LXa_y1E

kya_LXa_y1E

[Heracleum Persicum]

What would we see at the speed of light?

interesting , thanks

[Typhoon]

What would we see at the speed of light?

Excellent. +1

[Doc]

What would we see at the speed of light?

I listen to videos like this while driving. A lot of the time I learn more from listening to watching. But watching this video and thinking about it Traveling at the speed of light seemly collapses all dimensions except the dimension of travel.

[Doc]

https://www.youtube.com/watch?v=KZ8G4VKoSpQ

Deriving Einstein's most famous equation: Why does energy = mass x speed of light squared?

[Typhoon]

Physics World | Have scientists in Korea discovered the first room-temperature, ambient-pressure superconductor?

Room-temperature superconductivity has long been the holiest of holy grails in condensed-matter physics. Within the past decade, the appearance of new materials that superconduct at relatively balmy temperatures, but only under extreme pressures, has brought a slight yet significant alteration in the quest. To be truly grail-like, a newly synthesized superconductor cannot merely carry electrical current without resistance at room temperature. It must also do it at ambient pressure for it to have practical applications beyond the laboratory – such as levitating trains, efficient power lines or cheaper MRI machines.

So when a paper entitled “The First Room-Temperature Ambient-Pressure Superconductor” appeared on the arXiv preprint server earlier this week, physicists were intrigued – though also sceptical, given recent retractions and allegations of scientific misconduct in the field.

Now decades ago, pre-internet, I remember when a colleague showed up breathlessly holding the Pons and Fleischman "Cold fusion", still warm from the fax machine, preprint paper.

As I read it, I recall thinking, "Wow, if this proves to be valid, then this discovery would be comparable to that of fire". Unfortunately, it turned out that Pons and Fleischman had jumped to their conclusions a bit prematurely, to say the least.

A material that remains superconducting - able to carry electric current with no loss due to resistance - at room temperature would be as revolutionary as fire. In other words, a Promethean discovery.

[NapLajoieonSteroids]

The very slim chance it works is exciting, nevertheless.

If the green light is even given, I'm all set to dedicate the rest of my life to finding the most trivial application possible for the new technology.

[Doc]

https://muon-g-2.fnal.gov/

New results from the Muon g-2 experiment at Fermilab will be unveiled in a scientific seminar on August 10

[Typhoon]

https://muon-g-2.fnal.gov/

New results from the Muon g-2 experiment at Fermilab will be unveiled in a scientific seminar on August 10

Thanks for the update.

A friend, retired from the field, and I were recently talking about the muon g-2 experiment.

He noted that the most recent run had been completed for some time now and was wondering "Where's the results?".

Also wonder what progress, if any, has been made is resolving the significant disagreement between the two theoretical methods of calculation of the muon g-2 value.