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I tend to forget biologists are sooo carbon-centered...

Of course. Watch out for things like, \use_package amsmath 1 \use_package amssymb 1 \use_package cancel 1 \use_package esint 1 \use_package mathdots 0 \use_package mathtools 1 \use_package mhchem 1 \use_package stackrel 1 \use_package stmaryrd 1 \use_package undertilde 1 etc on your headers, that some of these editors automatically generate but doesn't 'tell' you about. Good point.

Well I must say that video seemed to make perfect sense to me, as a total non-expert in this area. Sabine's key point seemed to be that there is a vacuum energy inherent in GR that is just a constant of nature, arising purely from GR in a self-contained way, with no connection at all to the energy of vacuum fluctuations in QFT. Is that controversial?

It is the part where it says "No twin paradox in an absolute frame of reference" https://en.wikipedia.org/wiki/Twin_paradox#No_twin_paradox_in_an_absolute_frame_of_reference It takes away his absolute immobility, he becomes stationary for everyone, it no longer has any state of motion ---------------------------- Who cares what you states ? it has no authority, unlike a public text read and corrected by dozens of people including university professors. You don't seem to know that a non-inertial frame changes speed relative to the outside world while a gravitational field is stationary. ------------------------------ The path you speak of is the elapsed time in the traveler's frame of reference, the fact that it is a path in space-time is a mathematical invention, not a physical reality. All we can deduce is that an object that moves MORE in space ages less. But there can exist a unique reference frame relative to which the speed of light is c, and therefore it would make sense to talk about the speed relative to waves because it would depend on the chosen measurement reference frame, if this is not the unique reference frame, this speed will be different from c. This is Lorentz theory. A gravitational field is stationary, an acceleration is not. In a gravitational field time flows more or less quickly in space, in an acceleration time always flows in the same way in space, the object which accelerates does not have the power to change the the flow of time around it, what's more, the Doppler effect perceived by the one accelerating is a kinematic Doppler effect and not a gravitational one, it comes from the fact that the objects move in relation to it.

There may be a way around this issue if we - as indicated by Mordred - if we really differ on the vacuum energy and the vacuum energy density. Where the vacuum energy is the total amount including virtual particles/ fields and so that any cosmic stray volume may hold. (Doesn't this view end with the vacuum catastrophe?) -Where the vacuum energy density represents any stray universal volume free from all the known elementary particles. I.e. calculating only with the absence of visible matter and the seemingly "empty" space. The vacuum energy (density or not) still remains confusing for me. And adding the VEV of the Higgs field the universal vacuum situation becomes even more enigmatic. It really looks like we should have use for some physics theory updates. /chron44

You also have to worry about whether particular codes are recognised on this site... some aren't. So even if you write something using a LaTeX editor and everything looks fine, some of it may not be recognised when transferred to this site. Thus, it is always a good idea to test something you've not used before in The Sandbox before posting it in a thread for real.

Hi, I understand that the VEV is the (lowest) "strength" at which mass comes to existence or is revealed (where the intrinsic mass is activated for all massive particles). And Higgs field is an energy field that permeates all the universe. Also that the vacuum energy or the vacuum energy density (is there a difference?) have been measured or observed. (If so, then I mean the vacuum energy density.) Though to my knowledge VEV is although discovered (LHC) and calculated via some of the formulas Mordred is providing giving the amount of about 246 GeV. Although, if using the ChatGPT3.5, it says that VEV quote "It represents the minimum energy configuration of the Higgs field and is a fundamental property of the vacuum." -That Higgs field energy never is going under this value in entire universe. So one of you (or both) are separating on the lowest energy associated for manifesting mass, VEV. -And the ChatGPT..?? which is declaring that VEV - also - is "a fundamental property of the vacuum". I.e. not only being a strength or an "effective_action" applied on intrinsic masses. I believe that my quest remains. (Though the ChatGPT may lure or confuse me when it says that VEV is a "fundamental property of the vacuum" when it really only is meaning that VEV is the lowest universal/ vacuum energy constant at which mass is manifested at.) /chron44

I find it quite bizarre that some people regard it as significant that the image on a retina is upside down. It's like wondering how the images on a DVD are turned upright on a TV screen.

Technically yes, there will be some amount of frequency shift, though in practice the effect is quite small for a weak field such as the Earth’s. That’s hard to answer, since whether something is considered intuitive or not depends on the person. I kind of like the paths lengths way of looking at it, since most people can relate to it. Total accumulated proper time equals the geometric length of the path through spacetime, as I’ve mentioned already. The crucial point is that the two paths are not of equal lengths. I think you should read the article more carefully. I said there’s no rest frame to light, so it makes no sense to speak of “speed relative to waves”. There’s no tidal gravity in an accelerated frame, meaning that \[R_{\mu\nu}=0; W{^{\mu}}{_{\nu\alpha\beta}}=0\] and therefore \[R{^{\mu}}{_{\nu\alpha\beta}}=0\] However, there is a homogenous gravitational field due to proper acceleration locally, according to the equivalence principle. The Riemann tensor vanishes for such homogenous fields, so spacetime remains of course flat as expected. The metric in the accelerating frame, which now contains a term which is equivalent to a gravitational potential, is isomorphic to the Minkowski metric, also as expected.

And a more, shall we say, controversial ( as always ) interpretation of vacuum energy

If your certain of your equations and it's validity I'm sure your going to want to test them. If you think about it I provided the essential equations to do just that with a given dataset such as Planck. I certainly do when I model build or simply test and cross check any new relations/interactions. Those equations apply LCDM. to the cosmological redshift. As far as a new value of G well all I can say to that is good freaking luck on that score with what you have shown so far. this is a listing of the various types of studies and results form them for variations of G tests for spatial dependence is page 200 onward http://www2.fisica.unlp.edu.ar/materias/FisGral2semestre2/Gillies.pdf

His problem when you consider that a 9pi area over the integral of its radius is just 4 which is exactly what he's factoring in for the gravitational constant. And you should really use my optimization of the surface volume about an origin sphere instead because it isn't factoring in 4 it is factoring in 3.87553041018 that's only a 1.3% difference which adds up when you consider all of the angular momenta involved in the observation of gravitational bodies.

fair enough, something to keep in mind if your looking at cosmological redshift is that the expansion rates are not linear. The equation above shows this as the resultant is to determine the Hubble value at a given Z compared to the value today. The relations under the square root is the evolution of the energy density for matter, radiation and Lambda. You can learn these here. https://en.wikipedia.org/wiki/Equation_of_state_(cosmology) this related to the FLRW acecleration equations. described here https://en.wikipedia.org/wiki/Friedmann_equations that link supplies some very useful integrals with regards to the scale factor the evolution of the scale factor "a" using the above relations gives \[\frac{\ddot{a}}{a}=-\frac{4G}{3}(\rho+3P)+\frac{\Lambda}{3}\] however to get the FLRW metric cosmological redshift equation you will also need the Newton weak field limit treatments as per GR. Particularly for curvature K=0 if your interested in that let me know and I'll provide more details

I have no argument with that. He was not nearly as hyperbolic as Hitchens, and far more personable in the screen.

A=pi*3^2=9pi; A'=(2*3)^(2-1)pi the integral is (6pi/(1+1))^(1+1)=(6/2)^2 * pi=9pi If you have a radius of R around an inner circle with a radius of r and wanted to maximize the amount of space in that outer ring R and minimize what is in the center circle r you would say lim x->infinity f(R)=r+r/x ; x=r, meaning that R=r+1 I suppose Newton is some shadow program working on maths adjacent to me Also: Having to make some corrections here, the 5.121 number extruded another radius from the original radius of 3 inches. So let's so how close we are with 2.121 (I just went back in and realized I did my own math wrong it was 2.74 something that was the point). And yes I realized you can still fit 9 spheres inside the second iteration without all of their surfaces touching so it is like squaring the volume of a sphere to get a hypersphere. Shouldn't second guess myself.

Really ? Sometimes they seem very appropriate for any geopolitics.

Here is a simple to follow calculation of the expected vacuum energy, and comparison to the observationally estimated vacuum energy which results in the 124 orders of magnitude 'vacuum catastrophe'. It also provides clarification about Cosmology, universal expansion and the Cosmological Principle.

ok First off you have vacuum energy and vacuum energy density confused. The first case though not a useful form for energy density. The VeV is the vacuum expectation value VeV this isn't the density. This is a term describing the effective action https://en.wikipedia.org/wiki/Effective_action for Higgs the effective action is defined by the equation \[v-\frac{1}{\sqrt{\sqrt{2}G^0_W}}=\frac{2M_W}{g}\] here \(M_W\) is the mass of the W boson and \( G^0_W\) is the reduced Fermi constant. These are used primarily when dealing with Feymann path integrals in scatterings or other particle to particle interactions involving Higgs in particular dealing with the CKMS mass mixing matrix. So its not your energy density more specifically they describe CKMS mixing angles or Weinberg mixing angles. for the above without going into too much detail the mixing angles are \[M_W=\frac{1}{2}gv\] \[M_Z=\frac{1}{COS\Theta_W}\frac{1}{2}gv=\frac{1}{Cos\theta_W}M_W\] more details can be found here. Page three I'm starting to compile the previous pages now if you want the vacuum energy density the FLRW has a useful equation. \[\rho_{crit} = \frac{3c^2H^2}{8\pi G}\] if you take the value of the Hubble constant today and plug it into that formula you will get approximately \(5.5\times 10^{-10} joules/m^3\) if you convert that over you will find your fairly close to 3.4 GeV/m^3 which matches depending on the dataset used for the Hubble constant. The confusion you had was simply not realizing the VeV isn't the energy density. hope that helps. I won't get into too many details of the quantum harmonic oscillator via zero point energy but if you take the zero point energy formula and integrate over momentum space d^3x you will end up with infinite energy. So you must renormalize by applying constraints on momentum space. However even following the renormalization procedure you still end up 120 orders of magnitude too high. There has been resolutions presented to this problem however nothing conclusive enough. Quantum field theory demystified by David Mcmahon has a decent coverage of the vacuum catastrophe edit forgot to add calculating the energy density for the cosmological constant uses the same procedure as per the critical density formula.

Your 'connotes' is contradicted in the OP: ... like believing that the Conservative Party are going to win a majority at the next British general election. Or Trump 'won' the last US presidential election. Given the vociferous and frequently malicious nature of the attacks on evolutionary biology by the US christian right in particular, I think Dawkins strikes the right tone. Sufficiently punchy to attract the attention of the uncommitted, yet not sinking to the level of the opposition. Got to remember who the target audience is - it isn't to the regular contributors to scienceforums.net. We more than any should allow him his leeway and applaud his contribution. Personally, I'd have gone for the title 'Satanic Verses' but I understand someone else got there first.

Who cares what wiki states it's never written by a professor in the field involved. It's never been nor will ever be an authority in physics or any other science. Garbage not even close to being accurate regardless if your describing LET or SR/GR.. Tell me do even understand what an inertial frame is as opposed to a non inertial frame ? It's no different in LET and you cannot even describe LET correctly if you don't know the difference. Tell me many more pages will it take before you realize that you never convince anyone that you are correct when you cannot describe the theories under discussions without being full of errors? Everyone is literally forced to correct your errors to the point where discussing the Pros and Cons between the two theories simply isn't happening.

Oh sure, I actually agree here, I did note 'I personally go with "there is none"'. But it's like "proving a negative", hard to be absolute. (Back when I was busy (ha!) dropping out of University I went to exactly 1 philosophy lecture, and this was the topic.)

Hence "connotes" rather than "means". When people talk about delusions, they're not usually talking about religious faith. I do think Dawkins generally overstated the harmful effect of faith - but maybe not by much. It's not simple lack of proof of the existence of god(s): it's a preponderance of evidence contradictory to each particular claim of each particular religion; it's the implausibility of the stories in holy scriptures; it's the whiff of self-interest from the beneficiaries of religious observance. Yes, it can be considered reasonable to cling to illusions when reality is grim, and religion is not the only illusion we cling to.

Lack of proof there is a god of some kind, isn't proof that this god doesn't exist. There are also plenty of reasons why reasonable people find comfort in some kind of belief, including upbringing (indoctrination?) and nervousness at the unknown. Not that I'm agnostic, I personally go with "there is none", but I think it's a bit too strong to say "delusion". It did sell some books, though. (dimreepr, is the incorrect "you're" in your signature ironic?)

Carnivores eat herbivores, and sometimes other carnivores. This notion of producers and consumers seems overly simplistic. Like someone is applying a very rudimentary economic model to it.

Is that the part where it says “Therefore, the twin paradox is not actually a paradox in the sense of a logical contradiction”? Just saying this doesn’t make it so. ”It may be added that the whole change in the conception of the ether which the special theory of relativity brought about, consisted in taking away from the ether its last mechanical quality, namely, its immobility.” doesn’t support that notion neither does “We may assume the existence of an ether; only we must give up ascribing a definite state of motion to it”