@henceproved the orthodox view can be found everywhere, in any textbook, all over this site, and the idea is that there is no known or conceivable/ plausible connection between EM waves and de broglie waves (those found in the sch. eqn.). the unorthodox view is that this is utterly and completely mistaken and linking the 2 correctly is the key to progress/ 21st century physics, past the current impasse caused by or due to (overreliance on) compartmentalized/ reductionistic thinking.
> The test of a first rate intelligence is the ability to hold two opposed ideas in the mind at the same time, and still retain the ability to function. —Fitzgerald
@ZeroTheHero actually both positions characterized by me are extreme and credible work "in the middle" can be found. havent seen H&M ref will look a little... anyway the unorthodox pov is generally quite rare to run across, although scattered... am usually quite surprised to hear anyone with over 5K rep on the site express any interest whatsoever :)
"tiggers"? "postdoc"? actually have compiled a very long list of unorthodox work myself, am overdue to write latest survey/ summary, its quite substantial now, but unclear how close to a tipping point any of it is.
@ZeroTheHero 1 or some might say anything other than "shut up and calculate" is "convoluted" lol! but always refreshing to occasionally run into a devils advocate, or devils passerby :)
googling debierre leads to unusual angles. has a somewhat vague facebook page, but google mentions a phd... maybe a phd philosophy? how about this for a curve ball? Postmodern Theory Returns to Continental Europequillette.com/2018/05/26/…
on arxiv, lots of solid physics papers but seemingly none along the lines you mention. he does have some "BSM" beyond standard model interest but nothing very edgy it would seem. arxiv.org/search/…
thx for refs will continue to follow up. have a very long list myself have been dabbling in this subject many yrs now incl in this chat room. somehow we havent crossed paths yet.
Can Quantum Mechanics ever predict the future of a broken person's life? Can it say what does the future hold for them?
Is it ever possible to calculate the future by Quantum Mechanics?
@ZeroTheHero I think all people involved are in agreement about the fact that there is no position operator (not even Newton-Wigner-like) acting on photon states. This means that there is no naive wavefunction $\langle x\vert \psi\rangle$.
What they disagree about is whether or not it is meaningful to define variant "wavefunctions" that kinda-but-not-completely act like the naive wavefunction in many ways, except that there is still no real position operator for it, so you can't straightforwardly interpret it as a position probability amplitude on it's own.
You get purists that say "that's not a wavefunction" and you get pragamatists that don't really care (and probably find the purists annoying :P)
For instance, the stuff Hawton constructs has a "position" operator that's not a 3-vector.
What you get people now actually disagreeing about is what, exactly, these non-standard wavefunctions can or can not be used for, and what covariance properties the results possess.
I asked this question yesterday. I have a thin conducting spherical shell. Once it is charged, the electrons will evenly distribute on its surface. Bu right now, I am not supposing the charged shell to be made up of electrons. I am supposing the shell to be made of continuous surface charge density(σ).
Now by any kinds of reasoning or by any kinds of experiment, I have to show that surface charge density(σ) is constant all over the thin conducting spherical shell. Can you please guide me?
The potential has to be the same everywhere in a conductor. That's because if there was any electric field inside a conductor the free charges inside the conductor would move in response to the field. This would rearrange the charge until the field became zero.
The actual expression for the potential would be complicated because the potential is due to all the charge on the sphere and for an uneven charge distribution this would have a complicated dependence on $r$.
Sorry... I meant "V= ∫ σ f(r) dS ⟹ k V = ∫ (kσ) f(r) dS ⟹ V ∝ σ ⟹ V = constant σ ⟹ constant = constant σ ⟹ σ = constant." where V is potential at a free space point due to thin spherical shell................... What is meant by "actual expression of potential"? Is not the expression for potential "V= ∫ (σ/r) dS" same for all continuous surface charges in classical electrostatics?
does laws of thermodynamics applicable to microscopic particle?i mean in a quantum state ,actually i was reading a book who has this question ,i am not sure about the answer can anybody help?
@YuvrajSingh... Many of the laws of thermodynamics apply to statistical system in equilibrium. A single particle is not a thermodynamic system (for one there is no meaningful definition of "equilibrium" for it), but you'll have to be more specific about what you're trying to do if this doesn't answer your question.
@ACuriousMind ok ,what i meant was ,that there are different type theory descrbing about how are system work [ system refers to our nature] does laws of thermodynamics are well accepted in this theories ?
You can charge a positive object by adding positive ions to it. For example you could fire alpha particles at the sphere. In that case the positive sphere would end up weighing more than the negative sphere because alpha particles are heavier than two electrons.
Hi all. The thing is: I need a answer of comment but it's kind check my work so the people tend to do not answer. But this is precisely what I need right now. Can you give me a light?
I'm studyin,g for the first time, the Tensor Product of Vector Spaces. After the answer of a particular question, $[1]$, I think that I grasped the key point of the role of Quotient Vector Space; the answer is:
It's literally immediately from the definition of quotient. If $V/W$ is a quotient...
@HrishabhNayal I think it's a poorly defined question. If it said the positive sphere was charged by removing electrons from it and the negative sphere was charged by adding electrons to it then it would be obvious the negative sphere weighed more. But as it is the question cannot be answered.
hi everyone today I was watching a film where one of character as a physicist says 'energy and time is the best two things to define a state of matter or a particle .was he right ?if we know about energy and time of a particle can we define it's state or would we need some other factor too ?
@JohnRennie ions , electrons, and alpha particles have negligible mass when we compare with mass of sphere which has not mentioned.
hi everyone today I was watching a film where one of character as a physicist says 'energy and time is the best two things to define a state of matter or a particle .was he right ?if we know about energy and time of a particle can we define it's state or would we need some other factor too
@YuvrajSingh... The quote is nonsense. Sometimes energy defines a state uniquely, sometimes it doesn't. It's wholly unclear how "time" would correspond to a state at all. You shouldn't expect movies to make rigorous scientific sense.
@ACuriousMind I classify all states of matter and particles that way. For example, hydrogen is clearly the state of 56 MJ and approximately 35.7 seconds; because of reasons.
Well the hydrogen that I analyzed in my time-ometer.
@ACuriousMind Yeah that's something totally different. That's for measuring duration of time between events. To measure the time that a particle or state of matter contains, you need a time-ometer, which just directly measures the time content of the object, using... science?
If you associate a frequency to the total energy of your particle using E = hf that gives you a characteristic time equal to 1/f. I wonder if that has any physical significance ....
Hi, everyone. I was thinking about quantum-mechanics when the following thought came to me. Consider a particle like electron. By de-borgli equation, this electron has a wave equation $\psi$. Now we know that electron has mass but waves doesn't, so how do I account for mass of electron in the $\psi$ description. One way I thought a way out of this conundrum is the mass is irrelevant and only momentum is relevant,
and wave and particles both have momentum (although defined by different formula in each case). Is this the right intrepretation.
@henceproved Counterquestion: The state of a classical particle is completely defined by its position and velocity. How do you account for its mass there?
actually that what i wrote that mass should be irrelevant in physics in the last part of my statement. But somehow this statement seems to me a bit radical and hence wanted to confirm
actually mass controls the acceleration due to external potential. And also shrondinger equation has mass term, hence the evolution of wave equation is determined by the mass of the particle.
It's easy to do QM and become used to it being "weird" so that one loses track of which peculiarities are really quantum and which are general features of both classical and quantum mechanics. It's always instructive to look for the classical analogy, if one exists - either to see that it's the same, or to see how exactly QM is different.
"But one of the beautiful outcomes of our project so far has been the realization that at some deep level general relativity and quantum mechanics are actually the same idea" okay this is some serious nonsense
'elementary particles...are all assumed to intrinsically be point particles, of zero size. In our models, that’s not how it works. The particles are all effectively “little lumps of space” that have various special properties' I'm sure he's not doing string theory, and I'm sure he's not denying SR by pretending particles are rigid bodies, I'm sure this idea which physics literally can't bypass is somehow casually bypassed as if it's no gigantic deal or anything haha
yeah, I think his treatment on the GR side is shaky. Like you do not see a spacetime diagram, you only see a graph where space and time are independent axes, and that does not match what GR said
some of the ideas like entanglement are correlations however are not new and are quite explored in some background independent models, mostly stemmed from that EPR=ER conjecture of Carl Sagan
Aren't causal dynamics triangulation kinda similar to what he is doing, like, start with some abstract geometric object, give it some rules so they connect in certain ways, and then spacetime pops up?
though I don't recall many theories except string theory tries to explain particles
most background independent theories mostly deals with trying to reproduce GR, like loop quantum gravity weaving out spacetime from spin networks
Please be careful in answering homework-type questions. There are websites offering to write calculus exams for $300, amount to be negotiated depending on the grade required. Questions from the online exams are turning up on online sites.
I am amazed that my local supermarket can manage to keep their employees safe behind a transparent shield but that my university (well... pretty much all universities) could not manage to come up with something reasonable.
Also, what Semiclassical said - university is not essential, and students are not even employees, so I don't really see how you could make the moral case to coerce them to attend in person, even ignoring the legal problems
@ACuriousMind you can't do that anyways... I mean... practically you cannot force students to come to classes - at least I certainly don't manage attendence.
the question however is how does one balance the academic integrity of a program with the other imperatives of the situation.
and academic integrity was the big looser.
'cuz let's be clear... this doesn't end this year.
@ZeroTheHero Yes, but in normal times "attend this exam in person or fail the class" is a perfectly fine demand. I don't see it as nearly as defensible now.
I see we're talking academic policy - I figure we may lose a bit of learning as we require students to take classes remotely, but surely we'll be back in class by Fall.
Half the value of education is in the signalling, after all... :)
We've found that 13% of pregnant women in NYC are testing positive for COVID-19 and are asymptomatic, implying that 1 million New Yorkers already have it - herd immunity isn't too far off.
If you are from China or India, and went back home at some point before the travel restrictions, I'm not sure how realistic it is to expect you can take a final exam in the afternoon Eastern US time.
@AaronHall How does that contribute to herd immunity...? Positive but asymptomatic seems like it wouldn't really be herd immunity; plus you would need a much higher portion of the population than 13%...
I'm taking classes in NYC (started a new masters in stats) and we have lots of Chinese students, I met one from Wuhan even, and I don't believe anyone went to where the outbreak actually was...
@ACuriousMind maybe all calculus exams in North America should be at the same time (more or less)... doable over 3 times zones so that demand for exam takers locally overwhelms supply...
> The cosmic background radiation provides a rest frame for the Universe and we're all moving through it at 1/1000th the speed of light. - Stephen Wolfram
From Wiki: "Newfoundland, India, Iran, Afghanistan, Myanmar, Sri Lanka, the Marquesas, as well as parts of Australia use half-hour deviations from standard time, and some nations, such as Nepal, and some provinces, such as the Chatham Islands of New Zealand, use quarter-hour deviations."
@AaronHall No need to attribute it to Wolfram, that's a standard cosmology fact, cf. en.wikipedia.org/wiki/Cosmic_microwave_background#Features- What one could quibble with the is categorization of the CMB frame as "the universe's rest frame", but, eh, close enough.
I think somewhere in India has a 15 minute difference. Newfoundland is definitely 1/2 an hour off from "regular" time zones. It's where my company headquarters is at, so it messes with some timings when you forget they are slightly ahead.
@AaronHall skimming it now, am a decades long wolfram fan. hypergraphs are great but am dubious of them for modelling space/ physics; the emergent properties from "rewrite rules" he finds are remarkable but seemingly awkward/ unintuitive. however, this following idea (which he just cited in his blog) is very deep + promising + along the lines of my own decades of research: some basic CA rules can reproduce fluid dynamic like behavior. wolframscience.com/nks/p378--fluid-flow
I never even thought of that application! Off topic as non-mainstream? Post a late answer explaining that the question is just completely baseless; but provide no evidence of my own. That'll assert the mainstream dominance.
Can Quantum Mechanics ever predict the future of a broken person's life? Can it say what does the future hold for them?
Is it ever possible to calculate the future by Quantum Mechanics?
I'm studyin,g for the first time, the Tensor Product of Vector Spaces. After the answer of a particular question, $[1]$, I think that I grasped the key point of the role of Quotient Vector Space; the answer is:
It's literally immediately from the definition of quotient. If $V/W$ is a quotient...
Is there a solution manual for the third volume of Berkeley Physics Course (i.e. waves)? How I can find the answers? i really need it.
