/sci/ - Science & Math

no, coffee is not good for you

>>11694312
Is there any other credible scientists supporting this research. I’m certainly not one to argue science based on authority. But if this guy was onto something I’d expect a few people to support him, or at least consider his research credible. Even climate change deniers have a small group of educated supporters

>>11694416
that's not how it works anymore anon. until someone develops a fucking warp drive and demonstrates it by teleporting around the planet nothing fucking matters but circle jerking

>>11694312
>sci thread
>youtube links

Lmao

My ee professor taught us that it was invalid, but still useful. Is this not how it's normally taught?

>>11694312
This guy is dumb as a box of rocks.

>>11694447
Isn't that a different kirchoffs law?

>>11694447
wrong law retard

>>11694312
>>11694312
no fucking shit. circuit analysis is simplified maxwell's equations. simplified as in "let's ignore induction" etc. as long as you stay within the limits of model (literally like any physics model) it is a good description of what's going on.

>>11694312
Kirchhoff's law is literally saying "if you add these, you will get their sum" in a calculus kind of way.
Are you implying addition is wrong?

>>11694312
In the first video, he assumed emissivity was temperature independent. Does he have evidence of this?

>>11694574
Again, wrong law retard

>>11695729
*sigh* i'll take the bait. maybe somebody with an open mind will actually take something away from this brain damaged thread.

take maxwell's differential equation for the curl of E
[eqn]\nabla \times \vec{E} = -\vec{J}_m -\frac{\partial \vec{B}}{\partial t}[/eqn]
put it into integral form
[eqn]\oint_L \vec{E} \cdot d\vec{L} = -\int_S\vec{J}_m \cdot d\vec{S} - \frac{\partial}{\partial t} \int_S \vec{B} \cdot d\vec{S}[/eqn]
assume there is no magnetic current and rewrite the integral in the last term as a magnetic flux
[eqn]\oint_L \vec{E} \cdot d\vec{L} = - \frac{\partial \Phi_m}{\partial t}[/eqn]
assume the flux is tiny and can be ignored (this is mostly a good approximation for everyday electronics). recognize that the integral for E is the integral definition of voltage V
[eqn]V = -\oint_L \vec{E} \cdot d\vec{L} = 0[/eqn]
in words, if you go around a loop, the voltage is zero (ignoring induction). this is the kirchoff's circuit law.

>>11694312
>eu garbage
into the trash it goes

now, consider maxwell's equation for the curl of H
[eqn]\nabla \times \vec{H} = \vec{J}_e +\frac{\partial \vec{D}}{\partial t}[/eqn]
take the divergence
[eqn]\nabla \cdot (\nabla \times \vec{H}) = \nabla \cdot \vec{J}_e + \frac{\partial}{\partial t} \nabla \cdot \vec{D}[/eqn]
note that the divergence of a curl is zero and insert maxwell's equation for the divergence of D
[eqn]0 = \nabla \cdot \vec{J}_e + \frac{\partial \rho_e}{\partial t}[/eqn]
this is the continuity equation. it is a consequence of maxwell's equations, and not independent of them.
rewrite the equation as
[eqn]\nabla \cdot \vec{J}_e = - \frac{\partial \rho_e}{\partial t}[/eqn]
put it into integral form
[eqn]\oint_S \vec{J}_e \cdot d\vec{S} = - \frac{\partial}{\partial t} \int_V \rho_e dV[/eqn]
rewrite the last integral as total electric charge
[eqn]\oint_S \vec{J}_e \cdot d\vec{S} = - \frac{\partial Q_e}{\partial t}[/eqn]
assume the net charge in the circuit is constant (this is mostly a good approximation for everyday electronics). being constant, the time derivative is zero
[eqn]\oint_S \vec{J}_e \cdot d\vec{S} = 0[/eqn]
in words, if you track all of the current going into and out of a volume/node, it must sum to zero. this is kirchoff's current law.

you aren't going to win the nobel prize by finding holes in kirchoff's laws because they make assumptions to simplify maxwell's equations to make them easier to work with when designing circuits. of course, if you fall outside those assumptions, be prepared to do full wave simulations to understand what's going on. debate the validity of maxwell's laws all you want (even they aren't "reality") but i'm out

>>11694312
I only watched half of the last video. He describes a system of two boxes the smaller of which is "a perfect reflector" which is only coupled to the outer box through thermal conduction in the walls, not electromagnetic radiation.

If the system is not coupled to electromagnetic radiation of course it will not have a black body spectrum! There is no way for the electromagnetic field to come into thermal equilibrium with the walls of the system.

>>11695812
What's up with the retards ITT who think the OP is talking about circuit laws?

>>11695778
>>11695812
Wow you are a retard

>>11695829
They aren't retards. I knew what OP meant but I never hear of physicists refer to "Kirchoff's law" when they are talking about the black body spectrum.

>>11695844
Perhaps you should familiarize yourself with babby's first heat transfer, you ignoramus
https://en.m.wikipedia.org/wiki/Kirchhoff%27s_law_of_thermal_radiation

>>11695867
I have a phd in physics

>>11695870
Weird that a mechanical engineer with a BS knows more about thermal physics than you. Damn.

>>11695880
Look you must be OP. Read my comment a few posts above. I didn't take the time to even watch a whole video so it's possible I'm misunderstanding something, but it seems your hero is misunderstanding something very basic.

As for the terminology, I know what OP meant but I also know how physicists speak in practice.

>>11695887
>Look you must be OP
Im not. I didnt read the rest of your post.

>>11695890
Good for you. Bye then

>>11695891
You're gonna walk away still thinking that writing out Maxwell's equations was relevant to the thread. Hilarious.
>*sigh*
Kill yourself redditor.

>>11695898
I'm not that guy

Judging by the videos OP is talking about Kirchhoffs law of thermal radiation, not his circuitry laws

>>11694312
Electroboom and Walter Lewin already debated this. Lewin just probed poorly. KVL holds.

>>11695844
true, i have never heard of the radiation law, and i have a physics degree too. granted, my thermo class was the weakest link in my physics education.

>>11695927
You wouldn't necessarily have heard it even if it was a good class. Kirchoff's law was a somewhat qualitative statement that was important historically but he didn't find the exact form of the power emitted as a function of wavelength and temperature. That was found by Planck, and you have probably heard of Planck's law.

I mean the experiment is kind of interesting,but this guy seems like a weirdo

>affiliated with thunderbolts

aaaaaaaaaaaand dropped.

>>11694443
>i'm unable to comprehend information when it's presented in video format

Here you go, autist: https://z.zz.ht/xSW7e.pdf

>Kirchhoff’s Law of Thermal Emission asserts that, given sufficient dimensions to neglect diffraction, the radiation contained within arbitrary cavities must always be black, or normal, dependent only upon the frequency of observation and the temperature, while independent of the nature of the walls.

>With this in mind, simple tests were devised to demonstrate that Kirchhoff’s Law is invalid. It is readily apparent that all cavities appear black at room temperature within the laboratory. However, two completely different causes are responsible:

>1) cavities made from good emitters self-generate the appropriate radiation
>and 2) cavities made from poor emitters are filled with radiation already contained in the room, completely independent of the temperature of the cavity.

>The distinction between these two scenarios can be made by placing a heated object near either type of cavity. In the first case, the cavity emission will remain essentially undisturbed.

>>11695993

>That is because a real blackbody can do work, instantly converting incoming radiation to an emission which corresponds to the temperature of its walls. In the second case, the cavity becomes filled with radiation which is not characteristic of its own temperature. Contrary to current belief, cavity radiation is entirely dependent on the nature of the walls. When considering a perfect reflector, the radiation will not be black but, rather, will reflect any radiation which was previously incident upon the cavity from the surroundings. This explains why microwave cavities are resonant, not black, and why it is possible to acquire Ultra High Field Magnetic Resonance Imaging (UHFMRI) images using cavity resonators.

>Conversely, real blackbodies cannot contain any radiation other than that which is characteristic of the temperature of their walls, as shown in Planck’s equation. Blackbody radiation is not universal, Kirchhoff’s Law is false, and cavity radiation is absolutely dependent on the nature of the walls at every frequency of observation. Since they were derived from this law, the concepts of Planck time, Planck temperature, Planck length, and Planck mass are not universal and are devoid of any fundamental meaning in physics.

>>11695778
I remember writing exactly this in another thread about Kirchhoff's law months ago and got shit on for it.

>>11695993
>>11695995

CONCLUSIONS:

>For more than 150 years, Kirchhoff's Law of Thermal Emission [2,3] has governed much of scientific thought in physics and astronomy, despite the fact that it lacked proper theoretical and experimental proof (see [5–7] and references therein).

>Now it is clear that cavities do not all contain the same radiation independent of the nature of their walls. Perfect reflectors are unable to convert incoming radiation into the Planckian distribution corresponding to their wall temperature. In the absence of wall motion, they are unable to do any work and merely sustain the radiation in their surroundings.

>If this incident radiation is phase coherent, then perfect reflectors can even sustain standing waves, as required in both microwave telecommunication and Ultra High Field MRI [10, 11]. Had Kirchhoff's Law been valid, then neither of these modalities would exist, as no cavity would become resonant and all incident radiation would become destined to adopt the blackbody profile.

>Kirchhoff's Law is demonstrably false. Real blackbodies can do work on any incoming radiation and they do so instantly. They exclusively contain radiation which reflects the temperature of their walls, not the presence of the radiation in their surroundings. It is this ability to do work in the ideal blackbody, and the inability to do work in the perfect reflector, which determines the real behavior of cavities. That is also why laboratory blackbodies are always constructed from materials which possess relatively elevated emissivity values over the frequencies of interest.

>The production of a blackbody spectrum absolutely requires the presence of a vibrational lattice and is intrinsically tied to the nature of the walls, contrary to Kirchhoff’s claim.

>>11696031

>As a result, Max Planck’s long advocated universality [8, § 164] relative to time, length, mass, and temperature does not exist. The concept is absolutely dependent of the fact that Kirchhoff’s Law is valid and this is simply not the case.

>Physics thereby loses the universal significance of Planck’s constant and Boltzmann’s constant as well [17]. There is nothing inherently fundamental in these constants. They have no more primacy in nature than a mile would possess over a kilometer. Planck’s claim to the contrary is unfortunately unsound. The units of measure will forever remain a product of humanity’s definitions and science will always remain constrained by this realization.

>What happens when a law of physics fails an experimental test?

>There is a better understanding of the emissive properties of materials and, with it, the realization that the production of a thermal spectrum absolutely depends on the presence of a vibrational lattice [18]. Humanity can also continue to marvel at the wonders of microwave technology and the sharp images of UHFMRI as a constant reminder that Kirchhoff’s Law was false [10,11]. The realization that the experimental test presented herein invalidates Kirchhoff’s Law, mandates a fundamental reformulation of modern astronomy [19–24].

lmao this has been known since its exception you retard. There are limitations to every model and these limitations were always correctly communicated. Only you and that guy didn't get the memo apparently.
Wall of text shit thread. You probably didn't comprehend anything.

>>11694312
This has huge ramifications...

>>11696030
Makes sense

>>11694312
welp, there goes black hole theory and big bang theory

I love how everyone here dismisses it until some big brain academic acknowledges makes a nature article about it.(despite the guy being with all the accreditation and a phd but that doesnt matter on 4channel)
I can see the future retards here nodding in conformation that it was indeed invalid.

>>11697513
NPCs are real.

>>11697513
No big brain academic would acknowledge the points made by the guy in the Youtube videos. The guy is failing to understand the point of black body radiation but has a superiority complex and so thinks everyone else in the last 150 years has been wrong

>>11697631
>The guy is failing to understand the point of black body radiation
Entirely false. He demonstrates that he perfectly understands it, as opposed to you.

>has a superiority complex
Also entirely false.

What he has is a love for truth, and a disdain for misinformation being regurgitated as truth. He wants science to experience a Renaissance and an explosion in progress.

>>11696031
>despite the fact that it lacked proper theoretical and experimental proof (see [5–7] and references therein).
I KNEW IT, even before opening it..... I f****** knew those three would be worthless self-references. "Look, these articles written by me prove my point, what else do you need?"

>>11697513
>Dude why don't people believe just take the word of crackpots on the internet!?!
Bruh.

>>11698072
How is a crack pot allowed to hold a phd dude?
explain that

>>11698085
>dude all these phd's are part of an insane conspiracy to convince the world that aether doesn't exist
>but also having a phd means you're an infallible mega genius if you're contrarian enough

>>11697746
No he completely misses the point that black body radiation is about the electromagnetic field coming into thermal equilibrium with matter. This is why it is independent of the characteristics of the material. His "thought experiment" removes the coupling between these two systems so of course they don't come into thermal equilibrium. Still no one has replied to my post that pointed this out, so I don't know what you are getting at "as opposed to you." Apparently you don't even know which poster I am.

As for the superiority complex, misunderstanding something and then assuming you are right and that 150 years or so worth of physicists who have studied and built upon these ideas are wrong is a classic case.