The h Bar

John Rennie

15:08

Pizza!!

Slereah

bunny pastries are made

Now to cook them

I hope they don't turn out too bad

Didn't really have proper ingredients

Sha Vuklia

Guys, wikipedia says: "Brewster's angle (also known as the polarization angle) is an angle of incidence at which light with a particular polarization is perfectly transmitted through a transparent dielectric surface, with no reflection." However, isn't it true that it's only the parallel component that is zero? and not the entire field?

John Rennie

I suspect that's what it means by light with a particular polarization

Sha Vuklia

Well, the particular polarization should be that $E$ is perpendicular to the plane-of-indicence, no?

because that's what we use for these Fresnel equations

I have a better question maybe

o, no I don't actually

o wait

yea I am confused, but I think I'll figure it out

Sir Cumference

What is this duck on Stack Exchange

April Fools day is tomorrow

Secret

15:15

in Mathematics, 33 mins ago, by King Tut

How can we differentiate wrt x $\int_0^x \frac{u(t)}{\sqrt{x-t}}dt$

the limit at x does not even exists, yet wolfram alpha only spits out what f(0) is (where f is the integrand)

How are we allowed to ignore the nonexistent limit of f(t) at x when evaluating f(x)-f(0)?

Anonymous

Change that to $x-\epsilon$ maybe. Cauchy's principal value.

vzn

7 hours ago, by John Rennie

@Slereah the problem is not that John Duffield doesn't know any maths beyond school level, it's that he is proud of not knowing any maths beyond school level and contemptuous of anyone using maths beyond school level in physics. This sets a dreadful example to any students unfortunate enough to take him seriously.

↑ even someone who knows little math could have elements/ pieces/ glimmers of correct ideas that highly trained/ pro scientists/ physicists reject on incorrect grounds, mistaking (even mass) conventional wisdom for truth. education can lead to blind spots en.wikipedia.org/wiki/Shoshin

Anonymous

Oh please, vzn.

Secret

But his ideas need high level maths to be articulate properly

it's just too vague at its current state

vzn

@Secret new science is not built/ created instantaneously... emerging fully formed from the ether so to speak, that is a form of magical thinking... his ideas are far from vague for anyone impartial/ patient enough to engage seriously rather than flippantly with them o_O

Secret

15:22

He had proposed this idea for more than 3 years already, there is plenty of time for him to formulate his idea in a mathematical system so we can cross check with the experimental data

Sha Vuklia

What I’m confused about, is the following. The Fresnel equations for $r_\perp$ and $t_\perp$ are derived with the assumption that the electric incident field is perpendicular to the plane-of-incidence. At the Brewster angle, we have $r_\parallel=0$. We also know that the perpendicular part of the electric (perpendicular w.r.t. plane-of-incidence, or parallel w.r.t. interface as you wish), is continuous at the interface, so if $r_\perp=0$, why don’t we have $t_\perp=\pm 1$?

here $r_\perp,t_\perp$ are the Fresnel coefficients

Secret

(Let's take me) I already understood his basic idea, which is why I am more interested in the detailed implementation of his model

but he have yet to present one

vzn

@Secret he is not trained in higher mathematics, see it as something not unlike a disability he overcomes "otherwise" not unlike many around here with emotional deficits eg ADD, autism etc.

Anonymous

@vzn Example needed

Secret

@vzn Then please persuade him to get trained, his model will not be complete without precision

vzn

15:27

@Blue there are many cases of untrained scientists making major contributions from the field, alas, scientists tend to be unfamiliar with these cases, yet they are numerous... sometimes what happens is the simple discoveries are expanded by the "pros" & then original attribution can be lost in the shuffle...

Anonymous

@vzn I repeat: example needed

Anonymous

And don't tell me about Faraday. At least Faraday's intuition for physics was sound.

vzn

@Blue (admittedly) it is more common in the enlightenment period, less common in modern science.

Anonymous

"less common in modern science"

Tanuj

@Blue do you know how to remember color of those d block elements and their compounds (mainly coordination compounds) ? Sometimes , they seem to follow no logic whatsoever.

Anonymous

15:29

If you can cite even one of those less common examples, I will agree with you.

vzn

@Blue ...but not to be dismissed/ scoffed at entirely by impartial experts

Anonymous

@vzn See, you are again beating about the bush without any sign of solid evidence to back up your statement.

0celo7

John Duffield is no Faraday, give me a fucking break.

vzn

@Secret many of his models bear close resemblance/ are already highly expanded by minority/ contrarian experts, dismissed by other mainstream experts. aka moving the goalposts...

Society for Amateur Scientists

The Society for Amateur Scientists (SAS) was a non-profit 501(c)(3) organization dedicated to "helping ordinary people do extraordinary science". It was the first organization ever created for the generalists of citizen science. Rather than supporting a narrow interest, such as amateur astronomy or archeology, SAS supported amateur research into all fields of science and in so doing, it helped to launch the modern citizen science movement. == History == The Society for Amateur Scientists was the brainchild of Shawn Carlson, Ph.D, a physicist from the University of California, Berkeley's Center...

Secret

@vzn I don't think his way of understanding it is the same as those minority models such as dynamic ether etc.. I felt there is something original about his ideas

but at the current state it is too vague to see how those ideas fit with experiments (as all models must agree with experiments to be supported)

vzn

15:34

"amateurs" are lately very active in astronomy for example. many great examples there, the field is well suited for it. have cited quite a few in here myself over the years.

@Secret all new science starts out as "vague" wrt prior science esp as seen thru the eyes of experts.

Secret

@vzn but 3 years should be more than enough to come up with at least a fomulation of similar complexitiy as newtonian mechanics?

Anonymous

Visual astronomy doesn't require much mathematical background to get into, so it natural to find more amateurs there.

vzn

@Secret oh geez lol there is only 1 newton for good reason :P

Secret

but the formulation givenby newton is not very complex either. In fact, it is mostly high school maths as far the statements and basic applications of the 3 newton laws concerned

vzn

@Secret notice how none of the "experts/ professionals" in here have any comment on/ engagement with Tenev + Horstemeyer which you found yourself. youre an exception, "pre Phd"

@Blue its a scientific field. examples of "amateur/ citizen science" are widespread thru history/ currently if you open your eyes. alas "pro" scientists do not really pay much attn for "natural" reasons...

Anonymous

15:39

@vzn What's your point? I don't really understand. I already said amateurs making discovery in visual astronomy is not unusual. But making discoveries in fields like GR is ~~almost~~ impossible without mathematical background.

vzn

@Secret newton is one of the most brilliant physicists/ mathematicians in history and it is a misnomer that anything he did was simple. it is only simple in 2020 retrospect, an illusion created by the educational system that boils stuff down into a facade of simplicity & pretends it matches the original form.

@Blue yes. agreed. almost impossible. but not entirely inconceivable/ impossible. anyway JD himself says/ reiterates his ideas are not original!... they were/ are advocated by other top physicists past & present!

Anonymous

Strike-through to avoid misuse.

Anonymous

"they were/ are advocated by other top physicists past & present"

Anonymous

Proof needed.

vzn

@Blue he has listed numerous refs, the self-appointed experts in here refuse to engage with them, its much more fun to superciliously scoff at a crank

Anonymous

15:42

Anyway, I don't see this conversation going anywhere. Next time you make such vague statements bring along some proof.

Secret

@vzn well, I guess in the historical perspective, that will be true. But at least, JD should be able to write down some simple formula/ fractions for the various things he said, such as the equation that governs the bending caused by the variable speed of light in the ether for example (and the equation should then give the parabolic trajectory we observed)

vzn

@Blue the philosophy of science, being related to human affairs, is not subject to proof. next time you ask for proof try to avoid moving the goalposts along with everyone else in the room. "vagueness" is a projection. its easily/ facilely levelled by those who decline/ refuse to actually engage.

@Secret those eqns are indeed already written down. they are in (numerous) papers hes cited. eg Tenev + Horstemeyer. nobody really gives a ---- apparently incl you

Secret

@vzn nothing in that paper talks about light being of variable speed. It only talks about spacetime being an elastic medium and how that affect the motion of objects

vzn

← was gonna dig up 2 great recent amateur astronomy examples already cited in here, but guess the mood/ appetite for that has expired :(

Secret

> Notice that the shear wave speed will appear to have remained constant when
measured by an observer within the fabric, because the reduction in lapse rate
exactly compensates for the reduction in shear wave speed. This perceived invariance
of the shear wave speed is analogous to the speed of light invariance in General
Relativity.

vzn

15:48

@Secret lol (acc to them) light travels thru the spacetime fabric, an elastic medium, tenev+ horstemeyer dont have it all figured out yet either :P

Secret

their model also recovers the invariant speed of light, unlike in JD's comment that the speed of light is variable in the ether

so I think JD is talking about something else

vzn

@Secret maybe you are not too familiar with GR. the paper is pointing out/ proving that the model is basically equivalent to GR...

@Secret Tenev + Horstemeyer are implying the speed of light is not constant measured by observers that are not "local". that concept is rejected/ avoided in current physics. those measurements have already been carried out/ proven by Wineland relatively recent experiments/ citation JD gave (atomic clock speeds affected by gravity).

Secret

hmm...

this one?

nobelprize.org/nobel_prizes/physics/laureates/2012/…

vzn

aka cf also shapiro time delay he is fond of citing with good reason... en.wikipedia.org/wiki/Shapiro_time_delay

ACuriousMind

@vzn Your continued implications that people around here have "emotional deficits" are insulting, and comparing a lack of mathematical knowledge to autism or ADD is patentiy ridiculous and borderline offensive. Stop it.

5

Secret

15:56

sorry wrong paper: science.sciencemag.org/content/329/5999/1630

vzn

@ACuriousMind several chatters have self-identified as having autism/ ADD over the years. did not name any names. it was about having sensitivity to others disabilities.

Secret

ACM and all: I honestly don't care about (perceived) insults and emotions. It is this humanity of most people that makes them very inefficient at discussing issues

vzn

anyway, now skating on thin ice, will voluntarily leave. thx for the fair elements of discussion.

ACuriousMind

@vzn A lack of (mathematical) knowledge is not a disability.

3

Secret

This trait is one reason I can communicate with JD and some politicians, cause I ignore any avoiding questions, moving goalposts etc. and focus on the issue itself

vzn

15:58

@ACuriousMind others have insinuated/ nearly stated JDs lack of math knowledge/ expertise is like a disability

ACuriousMind

@vzn Where?

Secret

Now to get emotional:

ACuriousMind

Unless you have proof of that claim I'm gonna treat that as just another slander of the kind I just asked you to stop, and act accordingly.

vzn

@ACuriousMind lol try the starboard. dont think you will be fair about this & am going. have a nice day™

Secret

I sincerely think society should stop worrying about emotions and keep focus on the issues to be solved (unless where emotion is necessary). All these conversations that go nowhere is getting really boring

/end emotional

ACuriousMind

16:01

@vzn Ah, so once again you have no clear point to make. Well, maybe take a day off chat entirely to reflect on your conduct here, you continuing this behaviour is both disruptive and unacceptable.

@SirCumference In some time zones it is already April 1st right now.

SE usually runs their April's fools joke from the first possible to the last possible moment in which it is April 1st somewhere.

@0celo7 I see you already bought it :P

Slereah

@ACuriousMind what reference frame?

Secret

Earth's rest frame?

that seemed to be the msot logical choice for time zone assingments

ACuriousMind

@Slereah Is there a frame beside Earth's frame in which the concept of "date" makes sense?

(Discounting the Federation's stardate, of course :P )

Slereah

@ACuriousMind Well you can easily translate it into any frame

Secret

e.g. on a bus for example, that's a moving frame despite on the earth's surface

:P

ACuriousMind

16:11

@Slereah I'm not convinced you can!

Secret

in fact, even people just walking around is already an easy example of a moving frame, which can shift timezones by some negligible amount

Slereah

Just take the foliation of your spacetime, take a family of timelike curves orthogonal to them, define seconds on those the usual way, and take one of the slices as the origin

ie the birth of our lord Christ

Given freedom of foliation, it's always april first somewhere

Secret

you are talking about trying to define our time in schwartzchild coordinates (earth is approxmately schwartzchild if I recall)?

I am not convinced it is a good system

John Rennie

Since we're talking about GR let me give this answer a bit of well deserved publicity:

4

A: Does someone falling into a black hole see the end of the universe?

The currently accepted answer sidesteps the question about calculating what events can actually be seen using Schwarzschild coordinates. It is possible to find an answer to this question using Schwarzschild coordinates, both numerically and analytically. The answer of course is that the past ligh...

That's exactly the sort of well thought through and detailed answer that makes the PSE such a great place.

And it appears that, like buses, great answers come all at once:

2

A: Does someone falling into a black hole see the end of the universe?

Inspired by a similar question, I've been working on this topic at the same time as Rob Jeffries. Irritatingly, he beat me to it; but since I use a slightly different approach and since I don't want my efforts to be in vain, I'll post my own derivation. If nothing else, it serves as a confirmatio...

Sir Cumference

Welp, it's Passover and I have to go 10 days without bread. At this rate I'll lose 15 lb by the time it's over

Slereah

16:23

I guess technically, there is an infalling observer who will see the end of the universe

but I think it would be an infinitely accelerated observer

John Rennie

@Slereah you mean the one that starts at infinity? :-)

Slereah

@JohnRennie No, just one who goes so fast he ends up at the "intersection" of the singularity and timelike infinity!

Secret

@JohnRennie interesting, so the finite speed of light does restrict the amount of information that can reach an observer even if the spacetime geometry near the event horizon is so warped that asymptotes form

Slereah

But I don't think an observer with bounded acceleration can reach that point

John Rennie

The only downside is that it has cost me 1,000 rep points :-)

Slereah

16:26

I don't even think a Rindler observer could do it

Secret

you have tons, you will get them back soon enough

Slereah

since the observer only has a finite time to travel

Maybe I should try to calculate it and answer

Just to be contrarian

although even then, he would only observe the region I of the Schwarzschild spacetime!

Secret

so, the above discussion suggests since no observers can practically get to the point such that they see the light of the whole universe, does that mean the scenario where an observer can be fried by radiation from the whole universe past and future when crossing (forgot) in a kerr black hole will be avoided entiely?

Lozansky

I have two definitions of the Schwartz class:

$\{\varphi \in \mathcal{C}^{\infty}(\mathbb{R} | t^k D^m \varphi(t) \leq C_{k,m}, \forall k,m \in \mathbb{Z} \}$

$\{ \varphi \in \mathcal{C}^{\infty}|(1+|x|^n)|\varphi^{(k)}(x) \leq C_{n,k} ,\forall k,m \in \mathbb{Z}, x\in \mathbb{R}\}$

Are they equivalent?

Anonymous

@DanielSank Question for you: quantumcomputing.stackexchange.com/questions/1529/…

John Rennie

16:29

@Secret no that's a rather different scenario. Remember that the Kerr and RN geometries (where this occurs) are static so the have to be infinitely old. The frying is due to light being focussed through the black hole from the universe to the infinite past.

The universe the other side of the black hole that is.

And of course that universe doesn't exist since 13.7 billion years \ne \infty

Secret

ah i see, right so for realistic black holes, the finite time of formation plus the finite age of the universe will give an upper bound on the radiation that can be focused through

John Rennie

No radiation can be focussed through because there is no previous universe for it to come from.

Secret

...I really want to catch up with GR, but I can only do so after my PhD. I found myself being torn apart in too many knowledge fields already recently, I need to figure out how to stay focus...

John Duffield

@JohnRennie : your post is offensive and abusive and false. I expect better from a room owner.

Akoben

What is your PhD in Secret?

Anonymous

16:36

@Secret I want to learn during the summer vacations. We could do it together :P

Secret

@Akoben computational chemistry and organic metalic catalysis for my field

Akoben

Ahh heh

That is quite far from GR :)

Anonymous

I had started watching this playlist: youtube.com/playlist?list=PLtku678e9yj725K6hjLqKhJ854nTWWR5e

Secret

@Akoben I have done undergrad physics including EFE solving classes before, but I was so confused thus I performed poorly

Anonymous

But had to stop due to shortage of time

Anonymous

16:37

Was pretty good

Anonymous

@Secret What's EFE?

Secret

Einstein Field Equations

Anonymous

Oh, okhay

Akoben

@Blue

That's a great playlist

Slereah

Wait, no

Anonymous

16:38

@Akoben You watched it?

Slereah

unbounded acceleration observer still wouldn't do it, I think

Anonymous

I just went through the first few

Slereah

Unless...

Akoben

Yeah, when I started my PhD I watched a bunch

Slereah

I guess it would work if the acceleration became unbounded at the event horizon, perhaps?

Anonymous

16:39

There are lot of things I have in my bucket list, but instead I'm having to study semiconductor physics :P

Slereah

I'm not sure

Anonymous

@Akoben Oh cool, what's your PhD in?

Secret

As of 2018. I have the following interests and knowledge being learnt:
Contemporary fine arts
Australian politics
Philosophy (ethics, metaphysics (nothingness, reduction of being, ineffable, infinity, truth)
Mathematics (Various. suck at number theory)
Physics (Quantum mechanics, Classical mechanics, Thermodynamics, ...)
Biology (Microbiology)
Religion and beliefs (Baha'i, christianity, atheism)
Magic
Worldbuilding
Game development

Slereah

Except actually, I think if the acceleration becomes unbounded at the horizon, it never actually crosses it

So it's probably still true

Secret

The result: Insane procrastination (currently localised in the chat however)

Anonymous

16:44

Hmm, I realized learning at most 1-2 extra things at a time is better than trying to learn so many

Anonymous

That's why I put them off

Slereah

(although that observer would still see the entire universe, but this is for different reasons)

Secret

yeah in order to prevent my own life from being f888ed up, game development, worldbuilding is currently put on hold, whereas for the others, they are mostly learnt from conferences and interacting with uni clubs

My strongest interest (which I called my purpose of life) is to unlock the mystery of nature. I am intrinsically curious, and I want to understand nature in its entirely, but to do so, I need to be well versed in all domains of human knowledge

The intermix of ideas from different domains is my habit and also my strengths

Anonymous

Well, sort of same here, except that I don't keep hopes that I'll be ever able to "unlock" it :P

Anonymous

It's just fun learning a variety of things without being restricted

Secret

16:49

and of this entire universe, there is only one thing I hate

John Duffield

@Blue :it's true. When you lift up the electron you do work on it. You add energy to it. You increase its mass. When you drop it, gravity converts some of the electron potential energy into kinetic energy, which is typically dissipated, then you're left with a mass deficit, and you're back where you started: And I quote:

"This lost energy, necessary to overcome the potential barrier to separate the objects, is the binding energy. If this binding energy were retained in the system as heat, its mass would not decrease, whereas binding energy lost from the system as heat radiation would itself have mass. It directly represents the "mass deficit" of the cold, bound system".

Secret

@Blue that's true

John Duffield

@Secret : what isn't true are those "cherry picking" allegations. Einstein said what he said.

Akoben

@JohnDuffield You don't increase its mass though

Secret

@JohnDuffield As I mentioned, it has been more than 5 years, I don't know how much you changed

John Duffield

16:53

@JohnRennie : we have a "be nice" policy in this chat room. That especially applies to room owners.

@Akoben : you do increase its mass. Read the Wikipedia binding energy article.

@Secret : I haven't changed much. What Einstein said hasn't changed at all. The thing to appreciate is that some people will tell you something about relativity that flatly contradicts Einstein, then when you point it out and link to what Einstein did say, they say "oh that's just cherry picking".

Akoben

@JohnDuffield ahh sorry, I see you are talking about the effective mass of a nuclei, I misunderstood and thought you were talking about an electron

John Duffield

@Akoben : I was talking about an electron. It's the simplest "body" you can use in this sort of gravitational situation. It's mass also varies when it forms a hydrogen atom with a proton. The proton's mass varies too, but not so much. The binding energy is typically 13.6ev, most of that is lost from the electron's mass-energy.

ACuriousMind

@JohnDuffield We also have the policy that when there are users whose behaviour elicits overwhelmingly negative responses in other users, the problem may lie with that user, not with the users responding. You don't get to goad people into "not nice" responses and then smugly cite Be Nice at them.

11

Akoben

@JohnDuffield Then you aren't correct. The electron is a fundamental particle with an intrinsic, Lorentz invariant mass that can't be changed under any circumstances without it no longer being an electron.

ACuriousMind

It is a matter of record that many of your views about physics are idiosyncratic, to say the least, and rejected by most users around here as wrong or misguided. Pointing this out to other users is not a violation of Be Nice, and in fact the logical extension of our main site's non-mainstream policy.

10

John Duffield

17:02

@Akoben : I'm sorry Akoben, it just isn't true. You can work this out for yourself. Imagine you drop an electron into a black hole from a great distance. By how much does the black hole mass increase?

Akoben

Fundamental particles are essentially classified according to their mass and their spin: how high do you have to 'lift up an electron' until it becomes a muon?

John Duffield

@Akoben : you can't convert an electron into a muon by lifting it up. The extra mass-energy is quite small. Take a look at that black hole situation. What's the black hole mass increase?

Akoben

The rest mass of the elctron, if you drop it in at asymptotic infinity at rest

DanielSank

@ACuriousMind true as that may be, John's comment was offensive in the sense that you explained to me that one time.

Secret

@DanielSank but what are our choices?

DanielSank

17:06

Public service announcement: this chat room has an "ignore" feature.

John Duffield

@Akoben : so the black hole mass increases by 511keV/c²? Yes? That's what I'd say the mass increase was?

Secret

@DanielSank the issue here is that new users get mislead, and new users don't necessary know what to do. That's one example of a loophole that the ignore function cannot handle

DanielSank

It will be interesting to see if we need to amend policy to deal with "frequent stipulation of scientific misinformation".

@Secret ah yes. I just had the same thought.

This is not good and should be considered.

Akoben

@JohnDuffield Yes

DanielSank

@Akoben are you "new"?

John Duffield

17:08

@ACuriousMind : some of my views are correct, and some users are abusive about those correct views.

Secret

I hate being ignored, thus I knew tons of loophole to many shadowbanning, ignoring whatever countermeasures

Akoben

@DanielSank No, just not very active :)

DanielSank

@JohnDuffield most of what you post here is nonsense, in the judgement of many users. It is an interesting situation.

Secret

LEtme check if there is a meta on that misinformation issue...

DanielSank

@Secret good idea

Akoben

17:10

@JohnDuffield I'm not sure I understand what you are saying. Are you implying that the mass of the electron increases in that situation?

John Duffield

@Akoben : OK, agreed. So what about the electron's kinetic energy KE=½mv²? The electron ended up travelling quite fast, and conservation of energy applies.

Secret

::finally, an equation::

5

Akoben

I can ignore the KE by choosing to do all my calculations in the rest frame of the electron.

John Duffield

@Akoben : when you drop the electron, some of the electron's potential energy is converted into kinetic energy. And that potential energy is the electron's potential energy. It's mass energy.

Akoben

What do you mean electrons potential energy?

John Duffield

17:14

@Akoben : I'm sorry, it's wrong to ignore it. Conservation of energy applies. You start with a 511keV/c² electron, you get a fast-moving electron with considerable KE=½mv² but the black hole mass increase is only 511keV/c².

Secret

@DanielSank I don't think we have something in the phrasing of misinformation, the only closest one being the handling of certain claims:

6

A: How can we combat arrogance and ignorance on physics stack exchange?

The question of how to decide what is right and wrong in science is a vexed one and always has been. The current approach is peer review, but of course the problem is how to select the peers. Eminent scientists have been wrong in the past and will be wrong again, so ultimately no-one’s judgement ...

Akoben

Energy conservation is $E^2 = m^2 + p^2$, with $m = 511keV$ and is perfectly satisfied.

John Duffield

@Akoben : Imagine you're on Earth. If you fire an electron upwards at 11.7km/s you're giving it considerable kinetic energy. This is enough for it to escape the Earth's gravitational field. As the electron ascends its kinetic energy is converted into potential energy, But the electron "escapes the system". It takes that potential energy away with it.

Akoben

And you call that potential energy mass?

John Duffield

@Akoben : yes. See the above scenario. The electron that escapes the Earth's gravitational field has more mass than the electron at the surface of the Earth. The difference equates to kinetic energy of 11.7km/s. Again, see the mass deficit section of the binding energy article. It doesn't just apply to bricks etc. It applies to electrons too.

@DanielSank : it will get even more interesting when you come to appreciate that most of what I post here is correct.

ACuriousMind

17:29

@JohnDuffield That sort of grandstanding but pointless claim is precisely the kind of bait - a statement designed to aggravate other users and get them to argue with you - I was talking about.

Anonymous

I love the confidence though ;)

Sha Vuklia

Guys, I don’t understand how they get at 4.59. They say that they multiply by $c$, but the formula for the incident irradiance is $I_i=1/2v\epsilon E_{r0}^2$, so multiplying by $c$ would give $cv$, which doesn’t equal $n=c/v$? They also couldn’t have meant that they were actually dividing by $c$, because that would have yielded $1/n_i$? And I also don’t understand why we have $n_i$ in front of the transmission part, while I would be expecting $n_t$ there? Could someone clarify the step for me?

Secret

@Blue overconfidence can be bad for strifing for mutual understanding

John Duffield

@ACuriousMind : it isn't grandstanding. I'm correct about this mass deficit thing, and yet people scoff. Then when I try to back it up with references and explanation and pointing to conservation of energy, people like Blue still scoff. This is not good.

Secret

@JohnDuffield Acuriousmin is not referring to the stuff you made above, but this particular comment:

10 mins ago, by John Duffield

@DanielSank : it will get even more interesting when you come to appreciate that most of what I post here is correct.

Anonymous

17:34

I already explained a long time back why your mass deficit theory is rubbish. No mainstream physicist would agree with theories like "electron's mass changes if you lift them up"

Secret

This comment really contribute no information to the discussion

ACuriousMind

@ShaVuklia Hey, long time no see :) I'm afraid optics is much less my thing than mechanics, so no idea what's going on there at a glance :|

Akoben

@JohnDuffield Imagine you were freely falling into a black hole with the electron. You can now continually measure its mass as you both fall in. Do you measure different masses the closer to the BH you get?

John Duffield

@Blue : it isn't my mass deficit theory.

Anonymous

@JohnDuffield The conclusions are your own.

2

Sha Vuklia

17:35

@ACuriousMind yea it's been a while! too bad, but thanks for letting me know, I will ask on the main forum then

John Duffield

@Akoben : you don't measure any mass difference because you are similarly affected.

Prathyush Poduval

@ShaVuklia I may be able to help you

lemme go thorugh it once, its been quite some time

Akoben

What do you mean you are similarly effected?

Sha Vuklia

alright cool! @PrathyushPoduval

John Duffield

@Blue : they aren't my own. The mass deficit is is bog standard relativity. Gravity is not a force in the Newtonain sense. It isn't my fault it doesn't square with what's taught in schools.

Akoben

17:37

Mass deficit of electrons is definitely not standard relativity.

Anonymous

"taught in schools" . Okay, trying stating that theory in a Physics SE post. You'll find the mainstream physicists rushing to point out why your theory is wrong. I don't even have to do anything. dcmkee also explained it to you a long time back as to why it is wrong, but you seem to be stuck with your wrong notions.

John Duffield

@Akoben : I fall faster and faster, and as I do some of my mass-energy is converted into kinetic energy. Ditto for my measuring equipment. So I don't measure any mass change.

Secret

but standing on earth is no longer free falling, no?

Prathyush Poduval

@ShaVuklia Isn't the energy per unit area given by $\frac{1}{2v\mu_0}E^2$?

That would fix things up

Sha Vuklia

let me see, it could be equivalent

Prathyush Poduval

17:40

Becuase since you're involving $\epsilon$ instead of $\epsilon_0$, you need to deal with that too

lemm see.... $\sqrt{\frac{\epsilon}{\epsilon_0}}=n$ right?

Sha Vuklia

o, I actually haven't seen that, but I guess it's possible?

John Duffield

@Blue : dmckee hasn't explained why it's wrong.

Prathyush Poduval

Yeah it is

Sha Vuklia

alright

Prathyush Poduval

the velocity of light in a medium is given by $v=\frac{1}{\sqrt{\epsilon\mu}}$

Akoben

17:42

@JohnDuffield Is the same true with the electromagnetic force? Do you lose mass as you travel towards a charged object? Or do you lose charge?

Anonymous

"Yes. If you lift an electron, you do work on it. You add energy to it. You increase its mass." No. The system has more mass if the energy for separation came from an external source (or the same mass if the energy interaction was purely internal), but the electron continues to have exactly the mass it had before. — dmckee ♦ Mar 11 at 18:28

Prathyush Poduval

But $\mu\approx\mu_0$

Sha Vuklia

o yea, that sounds familiar

Prathyush Poduval

Yeah, substitute that and you get my formula for the intensity :-)

Sha Vuklia

that's impossible, because we would get a square root?

maybe you meant $v^2$?

Prathyush Poduval

17:43

Where?

Sha Vuklia

$\frac{1}{2v^2\mu_0}E^2$

John Duffield

@Akoben : yes. The electron loses circa 13.6ev when it combines with a proton to form a hydrogen atom. The proton loses a little mass, but not much. Charge is conserved. Sorry I have to go I'm afraid. Time for tea.

Prathyush Poduval

@ShaVuklia Thats a problem dimensionally. It's the formula for the energy per unit volume

Sha Vuklia

o no, you're right indeed

I forgot the factor $v$

I see it now

Prathyush Poduval

Yeah

dealing with electromagnetic materials is a huge pain in the a** for me

Sha Vuklia

17:46

but how do you use $n$ then?

Akoben

@JohnDuffield I think you are confusing effective theories with fundamental ones. It might seem as if the electron loses mass, but fundamentally it can't change its mass due to Lorentz invariance.

Sha Vuklia

ohh

!!!

I see it

Akoben

Enjoy your tea, I'm out too

Sha Vuklia

damn, thanks

Prathyush Poduval

@ShaVuklia $n=\sqrt{\frac{\epsilon}{\epsilon_0}}=\frac{c}{v}$

Yeah thats it

Sha Vuklia

17:47

cool, many many thanks:)) (again haha)

this saves me time

Prathyush Poduval

No problem!

ACuriousMind

@ShaVuklia <insert obligatory reminder that SE is not a forum here> ;)

Slereah

physics forum is a forum

hence the name

Sha Vuklia

so it's a.. community?

Slereah

it is a stack exchange

you go there

Sha Vuklia

17:51

lol

Slereah

exchange your stack for a better stack

Sha Vuklia

fair enough

o, I had never thought about the name

Prathyush Poduval

@Slereah stack???????

ACuriousMind

I got many nice stacks here

Sha Vuklia

what is the duck doing here then? also exchanging his 'stack'?

I smell a conspiracy

but I have to resume my work!

Prathyush Poduval

17:53

He's fooling us (the duck)

Sha Vuklia

cya

ACuriousMind

18:06

More seriously, the largest difference between traditional internet fora and SE is that SE wants to keep old questions alive and the duplicate system actively discourages bringing up the same topic again in a new thread, while traditional fora usually have rules against necroposting, i.e. resurrecting old threads with new posts or edits.

Anonymous

The largest difference is the UI :P

Anonymous

Reading posts on Reddit or Physics Forums is equivalent to torturing your eyes

Prathyush Poduval

yeah i agree with that m8

diobuc eulb

18:21

the ui is fine to me

dmckee

18:50

@Blue Well, there is a relationship between these two facts.

@SirCumference Aren't you allowed unleavened bread?

Not that I find many unleavened breads to be particularly attractive, but any port in a storm.

Anonymous

@dmckee Sure, there is some correlation between allowing editing/fixing of old posts and the general look of a webpage.

0celo7

19:23

@ACuriousMind pretty fun game.

skullpatrol

19:51

R.I.P. Sir Hawking.

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