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Hi OVAstronomy. Someone wrote this to me: "Time and space are infinite. Causality is infinite. Hubble's original equation is linear, so there must be some distance at which the speed due to expansion is greater than the speed of light ‒ which limits our observable universe to that distance as a radius. The hyperbolic tangent equation never exceeds the speed of light all the way to infinity, implying a universe infinite in space and time. It might also solve "the Hubble tension", where astronomers seem to be finding slower expansion rates at farther distances. The new equation predicts that observation as a mirage kind of effect. The expansion isn't really slower at farther distances, it just looks that way from here. We don't have to assume there's some sort of "dark energy" to explain it. I have yet to get an astronomer to tell me just what's wrong with my equation, which is weird to me. Normally they would be happy to point out my errors, and I might learn something." The equation: V(r) = c*tanh(H_r/c)
@@RazorM97 Hi, Time is not infinite as the big bang defines the beginning of time. When you refer to Hubble's equation, I assume you mean v = H_0 * d? This is only an approximation valid for small redshifts, as on larger scales general relativity must be accounted for, leading to a non linear relation. As dark energy domination continues, eventually objects will recede faster than light, leading to island universes in the late stages of the Universe. In regards to your equation, I cannot be certain what you mean as you have not defined your terms. Assuming that V(r) is a velocity, c the speed of light in a vacuum and H_r the value of the Hubble parameter at a proper distance, r, I can already tell you that your equation cannot possibly be correct based solely on a dimensional argument. A tanh function must have its argument (H_r/c) be dimensionless, as tanh is defined by exponentials - if the argument were not dimensionless you would not get a velocity or any physically meaningful result. The dimensions of H_r are inverse time (or frequency) and c is length per time. Hence the argument has dimensions of inverse length and so your equation cannot be correct.
Casimir explains how a waveguide works. The size of the metal plates determine resonance that can get in, while non-resonant frequencies fail to get in or out.
The problem with a cosmological constant and vacuum energy: The problem is vacuum energy is not the value described by cosmological constant it is far smaller value. The cosmological constant assumes that the vacuum energy must remain the same in every part of space as the space grows larger. There are a number of problems with this assumption. Number one is there is probability that when the vacuum energy is large enough that matter forms which does not annihilate. This would pull energy from the vacuum. Number two is the assumption is vacuum energy can violate the conservation of energy. This may be wrong. The vacuum energy may be borrowed from matter's energy field. The energy of the vacuum remains tiny if this is true. The reason is energy is given back to the energy fields of matter and does not increase the overall energy of the vacuum. The Heisenberg uncertainty principle coupled proceeding assumption would cause the vacuum energy to be an extremely small non-zero value at any given moment in time. The only exception to this would be when the universe was extremely tiny. The third problem is that vacuum energy is given an almost magical property of increasing as the space increases in the universe. This assumption is highly questionable as to be true. If the vacuum energy does not increase as the space increases then the vacuum energy must dilute. The fourth problem is if the vacuum energy does not decrease due to the expansion of the universe then gravity could not form or even exist today. The value given for causing the catastrophe is when the universe was expanding for the extremely tiny. It is not the value of vacuum energy today. The equation remains similar by sacrificing anything that makes any logical sense. If the vacuum energy does not dilute or decrease with time and expansion the model has no chance of matching what occurs. The rate the vacuum energy needs to dilute expediential amount as the universe expand from the extremely tiny. The Heisenberg uncertainty principle coupled with preceding assumptions would sets the lowest energy level of the vacuum energy. The lowest level for vacuum energy is were the uncertainty principle can remain true. The proceeding is concern wither not virtual particles exist or not.
I agree. Vacuum energy is an extrapalation of maths, which sometimes works, Diracs prediction of the neutrino, but failed with the UV catastrophe. Nature is not yet been proven to create something from nothing.
I think the framing problem may lie in a fundamental misinterpretation of quantum mechanics. The zero point energy does not describe a vacuum, it describes an empty space being measured. There is no way to establish energy without a complimentary time measurement, according to Heisenberg. Then, the vacuum energy is more properly framed as a vacuum NOT BEING MEASURED. How does one infer the properties of such a vacuum? It's by passing particles through it without measurement occurring, and this is is why General Relativity is giving better results towards vacuum energy. A quantum mechanical derivation of this kind of vacuum energy may be possible, but I think it might rely on a quantum mechanical description of the entire universe, which would then allow one to imply the state of the voids in cosmology. There's an even more fundamental form of vacuum - as a space where even theory hasn't been established yet. This, I think, is a good kind of vacuum to describe what's outside the horizon of the observable universe. It's worth thinking about nothing sometimes, and perhaps trying to categorize different types of nothing, by different approaches to theories of nothing. Typically these approaches have some truth to them, and it's a matter of contextualizing each theory of nothing appropriately.
2-H/12=0, H=10Pi/pm^4=3(D-1)=0 when D=1 : string, 10pi/pm^4/A=0.76*10^119, pm=1.67*10^-27 kg : proton mass, A=5.29*10^-11 meter, 2-3(D-1)/12=0 for 0 mass of photon, D=(24+3)/3=6+3 extra 6 dimension of string theory.
Distance in space and time as well as e.g. weight are derived attributes, while the ones we call “size”, “charge” and “information” are fundamental. How can size be fundamental when spatial distance is not? It’s because size is actually a result of a measurement that space can can make on an entity. How can information be fundamental when its only manifestation requires space and matter? It’s because matter is only a bridge for the information to spread in(to) our discoverable universe. In other words, space and matter are only transmitters FOR US to quantize size and get the information that builds up our elaborate structures but neither size nor information (nor “charge” or “potential”) requires space or time or matter to exist. How can charge/potential be fundamental when it requires space, time and at least some kind of matter? Ask the light! Take it as my prediction and see how well it will age.
Maxwell's demon is typically applied when considering classical thermodynamics - are you applying it here regarding the uncertainty principle and the fundamental limit on information of a quantum system?
Good trial video, You must have realized that Higgs is not virtual, as it is for fermions. Vanderwalls force is not exchange force but atomic or molecular in nature, microscopic in physics. Keep it up .
Even though hawking radiation almost likely impossible to verify due no one will be around by then, however numerous experience showed hawking radiation in sonic black hole experiments.
2:05 What is this "igen" term you're talking about? It's something I don't think I've ever heard of before; tried to do a quick search for it, but all I found was some apple looking 💩and some German stuff...
Eigenvectors or -states are an important concept in QM: especially eigenstates of the energy operator are stable in time, for example free particles of a field. An eigenstate of an operator is such that the state remains the same when the operator acts on it.
Isn’t electromagnetic force mostly caused by exchange of virtual photons? In that sense they are very “real” in that without them charged particles wouldn’t attract or repel each other.
@@OVAstronomy How do you imagine detecting them, even in theory? If a particle is part of a final state, it's real and not virtual just by definition. See the S-matrix and the notions involved.
We don't speak of things smaller that 1 Planck length unit (PLU). It's the opposite-1 PLU is the smallest _separation_ in _space_ where _separation_ and _space_ still make sense. Nothing can be smaller, at least in our current theories.
Your particle is moving _relative to what?_ Why is motion in the picture at all? Better consider a particle relative to itself-that is, one that's not moving at all. Now, a classical particle is point-like, with zero size, so the GR's answer is no-it gravitates, but has no “parts” that could interact with each other. A funky consequence is that the classical electron must have a horizon: it has no size, all its mass is at a point. As an exercise, so that you may brag that you did actual GR calculations: use the Schwarzschild formula to calculate it (wrong metric, but simple, and a good approximation, give or take couple orders of mag), then compare it to the Planck length-the smallest scale at which space still, as we currently think, makes sense.A quantum particle, on the other hand, is incompatible with GR: GR wants to know the particle's both position and momentum. We don't have a quantum theory of gravity. The best physical answer from the quantum POV is ¯\_(ツ)_/¯. But anyhow, masses of ordinary particles under ordinary conditions are too small indeed to take their gravity into account.
@@OVAstronomy …assuming that vacuum energy _is_ the source of cosmological dark energy. It's kinda salient to make such a connection, but this well may be because we have two very precise theories, and, naturally, want to connect them, _starting_ with the most obvious features. I suspect the connection exists, but it's may not be so obvious and direct. The vacuums of GR and QFT are very different (even allowing “GR vacuum,” a region of spacetime free of events, to be meaningful, which is already a fuzzy concept; think of Einstein's hole argument as treated by A Macdonald, 2001, DOI 10.1119/1.1308265), and each makes sense only in its own corresponding theory.
@@cykkm I would agree with you on that. Our attempts so far have fell short at connecting the two, but there is undoubtedly a theory of everything capable of explaining both and other unsolved problems.
It was never a prediction. That's simply incoherent banter. What theory was ruled out to cause conflict -- nada. Regardless the problem with the quantum vaccum does exist. Virtual particles are being tested via super powerful lasers but nothing yet has materialized as to whether they actually exist, the cassimere effect holds up but that still provides no definitive proof just that a force is present... Regardless pretty good video. 🎉
If you are checking if our discoverable universe is really expanding, you have to check the means by which the inflation is currently shown to us, which are the assumed rules and axioms of physics. If we stop considering space to be fundamental, then we can consider it virtually expanding or even coming into existence the same way we can open, magnify and close a picture on a computer screen without having to think that something is, indeed, was created, is expanding, or ceased to exist.
To try everything Brilliant has to offer-free-for a full 30 days, visit brilliant.org/OVAstronomy . The first 200 of you will get 20% off Brilliant’s annual premium subscription.
Hi OVAstronomy. Someone wrote this to me:
"Time and space are infinite. Causality is infinite. Hubble's original equation is linear, so there must be some distance at which the speed due to expansion is greater than the speed of light ‒ which limits our observable universe to that distance as a radius.
The hyperbolic tangent equation never exceeds the speed of light all the way to infinity, implying a universe infinite in space and time. It might also solve "the Hubble tension", where astronomers seem to be finding slower expansion rates at farther distances. The new equation predicts that observation as a mirage kind of effect. The expansion isn't really slower at farther distances, it just looks that way from here. We don't have to assume there's some sort of "dark energy" to explain it.
I have yet to get an astronomer to tell me just what's wrong with my equation, which is weird to me. Normally they would be happy to point out my errors, and I might learn something."
The equation: V(r) = c*tanh(H_r/c)
@@RazorM97 Hi, Time is not infinite as the big bang defines the beginning of time. When you refer to Hubble's equation, I assume you mean v = H_0 * d? This is only an approximation valid for small redshifts, as on larger scales general relativity must be accounted for, leading to a non linear relation. As dark energy domination continues, eventually objects will recede faster than light, leading to island universes in the late stages of the Universe.
In regards to your equation, I cannot be certain what you mean as you have not defined your terms. Assuming that V(r) is a velocity, c the speed of light in a vacuum and H_r the value of the Hubble parameter at a proper distance, r, I can already tell you that your equation cannot possibly be correct based solely on a dimensional argument. A tanh function must have its argument (H_r/c) be dimensionless, as tanh is defined by exponentials - if the argument were not dimensionless you would not get a velocity or any physically meaningful result. The dimensions of H_r are inverse time (or frequency) and c is length per time. Hence the argument has dimensions of inverse length and so your equation cannot be correct.
@@OVAstronomy thanks a lot!
Casimir explains how a waveguide works. The size of the metal plates determine resonance that can get in, while non-resonant frequencies fail to get in or out.
The problem with a cosmological constant and vacuum energy:
The problem is vacuum energy is not the value described by cosmological constant it is far smaller value. The cosmological constant assumes that the vacuum energy must remain the same in every part of space as the space grows larger. There are a number of problems with this assumption. Number one is there is probability that when the vacuum energy is large enough that matter forms which does not annihilate. This would pull energy from the vacuum. Number two is the assumption is vacuum energy can violate the conservation of energy. This may be wrong. The vacuum energy may be borrowed from matter's energy field. The energy of the vacuum remains tiny if this is true. The reason is energy is given back to the energy fields of matter and does not increase the overall energy of the vacuum. The Heisenberg uncertainty principle coupled proceeding assumption would cause the vacuum energy to be an extremely small non-zero value at any given moment in time. The only exception to this would be when the universe was extremely tiny. The third problem is that vacuum energy is given an almost magical property of increasing as the space increases in the universe. This assumption is highly questionable as to be true. If the vacuum energy does not increase as the space increases then the vacuum energy must dilute. The fourth problem is if the vacuum energy does not decrease due to the expansion of the universe then gravity could not form or even exist today. The value given for causing the catastrophe is when the universe was expanding for the extremely tiny. It is not the value of vacuum energy today. The equation remains similar by sacrificing anything that makes any logical sense. If the vacuum energy does not dilute or decrease with time and expansion the model has no chance of matching what occurs. The rate the vacuum energy needs to dilute expediential amount as the universe expand from the extremely tiny. The Heisenberg uncertainty principle coupled with preceding assumptions would sets the lowest energy level of the vacuum energy. The lowest level for vacuum energy is were the uncertainty principle can remain true. The proceeding is concern wither not virtual particles exist or not.
I agree. Vacuum energy is an extrapalation of maths, which sometimes works, Diracs prediction of the neutrino, but failed with the UV catastrophe. Nature is not yet been proven to create something from nothing.
Well made video on a deep issue in modern physics..I was searching this for a while!! So thanks in order!!
I think the framing problem may lie in a fundamental misinterpretation of quantum mechanics.
The zero point energy does not describe a vacuum, it describes an empty space being measured.
There is no way to establish energy without a complimentary time measurement, according to Heisenberg.
Then, the vacuum energy is more properly framed as a vacuum NOT BEING MEASURED.
How does one infer the properties of such a vacuum? It's by passing particles through it without measurement occurring, and this is is why General Relativity is giving better results towards vacuum energy.
A quantum mechanical derivation of this kind of vacuum energy may be possible, but I think it might rely on a quantum mechanical description of the entire universe, which would then allow one to imply the state of the voids in cosmology.
There's an even more fundamental form of vacuum - as a space where even theory hasn't been established yet. This, I think, is a good kind of vacuum to describe what's outside the horizon of the observable universe.
It's worth thinking about nothing sometimes, and perhaps trying to categorize different types of nothing, by different approaches to theories of nothing.
Typically these approaches have some truth to them, and it's a matter of contextualizing each theory of nothing appropriately.
2-H/12=0, H=10Pi/pm^4=3(D-1)=0 when D=1 : string, 10pi/pm^4/A=0.76*10^119, pm=1.67*10^-27 kg : proton mass, A=5.29*10^-11 meter, 2-3(D-1)/12=0 for 0 mass of photon, D=(24+3)/3=6+3 extra 6 dimension of string theory.
Distance in space and time as well as e.g. weight are derived attributes, while the ones we call “size”, “charge” and “information” are fundamental. How can size be fundamental when spatial distance is not? It’s because size is actually a result of a measurement that space can can make on an entity. How can information be fundamental when its only manifestation requires space and matter? It’s because matter is only a bridge for the information to spread in(to) our discoverable universe. In other words, space and matter are only transmitters FOR US to quantize size and get the information that builds up our elaborate structures but neither size nor information (nor “charge” or “potential”) requires space or time or matter to exist. How can charge/potential be fundamental when it requires space, time and at least some kind of matter? Ask the light! Take it as my prediction and see how well it will age.
This JUST what I have been lookin g for - EXCELLENT
You forgot to include the “Maxwell’s Demon” into the explanation. A crucial concept for blending the quantum world with the classical world.
Maxwell's demon is typically applied when considering classical thermodynamics - are you applying it here regarding the uncertainty principle and the fundamental limit on information of a quantum system?
What happens if we substitute the energy density of the CMB in for the energy density of the vacuum ??
Good trial video,
You must have realized that Higgs is not virtual, as it is for fermions.
Vanderwalls force is not exchange force but atomic or molecular in nature, microscopic in physics.
Keep it up .
Even though hawking radiation almost likely impossible to verify due no one will be around by then, however numerous experience showed hawking radiation in sonic black hole experiments.
Who made the "worst" prediction? When? Published?
Didn't think so...
2:05
What is this "igen" term you're talking about? It's something I don't think I've ever heard of before; tried to do a quick search for it, but all I found was some apple looking 💩and some German stuff...
eigen
eigen is german and means own (it's own)
Eigenvectors or -states are an important concept in QM: especially eigenstates of the energy operator are stable in time, for example free particles of a field. An eigenstate of an operator is such that the state remains the same when the operator acts on it.
Eigenvalues, eigenvectors, etc.
Thanks!
Thank you very much! Glad you enjoyed
Isn’t electromagnetic force mostly caused by exchange of virtual photons? In that sense they are very “real” in that without them charged particles wouldn’t attract or repel each other.
The exchange boson for the EM force is the virtual photon yes, but they have never been detected individually. We see their effects but not them.
@@OVAstronomy How do you imagine detecting them, even in theory? If a particle is part of a final state, it's real and not virtual just by definition. See the S-matrix and the notions involved.
@@thedeemon I don't think they could ever be detected directly as like you eluded to; they are not real, yet they have real consequences.
Quantum field is linear but vaccum energy is non linear
Vacuum energy work if you work energy without consider output
little things make big things even when the little things are smaller than 1 planck unit
We don't speak of things smaller that 1 Planck length unit (PLU). It's the opposite-1 PLU is the smallest _separation_ in _space_ where _separation_ and _space_ still make sense. Nothing can be smaller, at least in our current theories.
If a particle moved fast enough would its own gravitational field influence it?
Your particle is moving _relative to what?_ Why is motion in the picture at all?
Better consider a particle relative to itself-that is, one that's not moving at all. Now, a classical particle is point-like, with zero size, so the GR's answer is no-it gravitates, but has no “parts” that could interact with each other. A funky consequence is that the classical electron must have a horizon: it has no size, all its mass is at a point. As an exercise, so that you may brag that you did actual GR calculations: use the Schwarzschild formula to calculate it (wrong metric, but simple, and a good approximation, give or take couple orders of mag), then compare it to the Planck length-the smallest scale at which space still, as we currently think, makes sense.A quantum particle, on the other hand, is incompatible with GR: GR wants to know the particle's both position and momentum. We don't have a quantum theory of gravity. The best physical answer from the quantum POV is ¯\_(ツ)_/¯. But anyhow, masses of ordinary particles under ordinary conditions are too small indeed to take their gravity into account.
not when u consider gravity to be a property of space, not mass
@@tybeedave thought it was the bending of space time through mass?
@@3d1e00 Mass caused spacetime to bend and the bending of spacetime tells mass how to move.
@@OVAstronomy yeah so does that mean that a particle accelerating fast enough can be influenced by its own gravity?
Why are people always talking about the worst prediction ever as if it was true. Shouldn't we abandon stupid ideas that led to it?
QFT is excellent at predicting the energies in particle scattering experiments. So it is interesting that it is so far off on vacuum energy
@@OVAstronomy …assuming that vacuum energy _is_ the source of cosmological dark energy. It's kinda salient to make such a connection, but this well may be because we have two very precise theories, and, naturally, want to connect them, _starting_ with the most obvious features. I suspect the connection exists, but it's may not be so obvious and direct. The vacuums of GR and QFT are very different (even allowing “GR vacuum,” a region of spacetime free of events, to be meaningful, which is already a fuzzy concept; think of Einstein's hole argument as treated by A Macdonald, 2001, DOI 10.1119/1.1308265), and each makes sense only in its own corresponding theory.
@@cykkm I would agree with you on that. Our attempts so far have fell short at connecting the two, but there is undoubtedly a theory of everything capable of explaining both and other unsolved problems.
It was never a prediction. That's simply incoherent banter. What theory was ruled out to cause conflict -- nada. Regardless the problem with the quantum vaccum does exist. Virtual particles are being tested via super powerful lasers but nothing yet has materialized as to whether they actually exist, the cassimere effect holds up but that still provides no definitive proof just that a force is present... Regardless pretty good video. 🎉
?
If you are checking if our discoverable universe is really expanding, you have to check the means by which the inflation is currently shown to us, which are the assumed rules and axioms of physics. If we stop considering space to be fundamental, then we can consider it virtually expanding or even coming into existence the same way we can open, magnify and close a picture on a computer screen without having to think that something is, indeed, was created, is expanding, or ceased to exist.