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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”

There's been a bit of conflation in some replies between A.C. and D.C.. D.C. is conserved but A.C. isn't. So: V.H.F. A.C. whose effects are more obvious than 50Hz. You could have 100 meters of 50 ohm coaxial cable with 10db loss per 100 meters. Connecting A.C. power at say 100MHz 100V to the (resistive) cable gives I =V/R = 2 amps input (200W). Connect a 50 ohm resistive load to the far end and you'll get ~ 31.6V at 0.632A i.e. 20W output. If you use a 200 meter cable you'll get 10V at 0.2A i.e. 2W. The input is still 200W into 50 ohms. The current drops exponentially along the cable. The main power losses are I^R losses in the conductor, dielectric (insulator) heating and radiation from the cable. There is no A.C. current conservation; some of it charges and discharges the dielectric and current is also involved in creating magnetic and electromagnetic fields. One way of dealing with reactance is to consider the effect of a load impedance mismatch. e.g. terminate the cable with 25 instead of 50 ohms. This will cause a power reflection back into the cable to compensate for trying to connect a 50 ohm cable to a 25 ohm load. If 20W output then 20 *(50 -25)/(50+25)W i.e. 6.7W is reflected back into the cable and after attenuation 0.67W reaches the source. You'll get standing waves on the cable; every half wavelength (About 1.5m) you'll get maximum voltage and minimum current; between these nodes you get a minimum voltage, maximum current node. A.C. current can be created and destroyed without breaking conservation laws. Some energy is stored in various fields and doesn't reach the load; sometimes it's called imaginary power(it can be treated as 90 deg or sqrt(-1) out of phase with 'real' power) or reactive power(capacitors and inductors have reactance). This is sort of real; there are meters which measure forward and reflected power in coax cables... I didn't want to oversimplify too much; this post ended up much longer than I intended.

This is the FLRW metric \[d{s^2}=-{c^2}d{t^2}+a({t^2})[d{r^2}+{S,k}{(r)^2}d\Omega^2\] \[S\kappa(r)= \begin{cases} R sin(r/R &(k=+1)\\ r &(k=0)\\ R sin(r/R) &(k=-1) \end {cases}\] This is the redshift equation(cosmological) that gets used at all ranges as it takes the evolution of matter, radiation and Lambda. \[H_z=H_o\sqrt{\Omega_m(1+z)^3+\Omega_{rad}(1+z)^4+\Omega_{\Lambda}}\]

Nope animals are just consumers, it's the plants that are the producers.

Any clues? I was thinking early turkey tail but someone with more experience with turkey tail said it isn't because the underside of early turkey tail is always white Image number 4 is a different tree with earlier stage growth

The redshift has little to do with gravitational constant and we have means of testing redshift by understanding the processes involved. We can for example examine hydrogen which is one of most common elements in our universe and using spectrography. There is nothing random that isn't cross checked by numerous means involving redshift. We don't even rely on it as our only means of distance calculation. Quite frankly no one method works for every distance range. A huge portion of papers can be found studying the accuracy of redshift at different ranges and those cross checks using other means such as interstellar parallax. Same applies to luminosity distance. By the way the redshift formula you find in textbooks is only useful at short distances cosmological scale.

The mathematics simply says that the traveling twin's own time is shorter, it explains nothing. Moreover, the path taken by the twin is longer and not shorter, what is shorter is its proper time. You can call proper time a "path" if you please, that's not why it will be a real one, show me this "path" in the sky if you can. Yet, Wikipedia says that there is a paradox except in the case where we postulate a privileged reference frame. How do you know that there is no preferred reference frame where the light is isotropic? You can't know. There is no gravitational field in an accelerated frame of reference, we are in flat space-time, the distance between the accelerating object and the stars varies unlike in a gravitational field, the Doppler effect is therefore kinematic, not gravitaionnel. ---------------------------- I wrote "This is also how Einstein saw it, he thought that there was an ether which was stationary for everyone." It is called the relativistic aether, but it is also a luminiferous ether, it is the Lorentz ether deprived of its state of motion.

You don't know whether the redshift is higher than it should be or not if the problem is a lack of some sinusoidal application to factor in the proximity values of galaxy A and B relative to the observer as I explained earlier. So you don't even know whether the cosmic event horizon or CMBR is the oldest light that's had time to reach the lens or whether it is just a blending that makes objects invisible as the tip of the cone becomes infinitesimal.

Not really. He concluded that space has properties, but it’s not a medium that represents a preferred frame of reference, or is required for light. The aether he spoke of later is not the luminiferous aether of Lorentz theory.

No I don't think so. See the Wiki article: https://en.wikipedia.org/wiki/Time_crystal and especially this passage: Time crystals do not violate the laws of thermodynamics: energy in the overall system is conserved, such a crystal does not spontaneously convert thermal energy into mechanical work, and it cannot serve as a perpetual store of work. But it may change perpetually in a fixed pattern in time for as long as the system can be maintained. They possess "motion without energy"[16]—their apparent motion does not represent conventional kinetic energy.[17] I'll admit I know nothing about time crystals apart from what I have just quickly read, but it looks to me as if these things exhibit motion in their ground state. The definition of a ground state is it is the lowest energy state allowed for the system. From that it follows that energy cannot be extracted from the system (unless you break the system up, I guess, which would be a one-off exercise). You have much the same thing with the zero point energy in a harmonic oscillator, or, to give a real example, in the vibrational ground state of a diatomic molecule. There is still residual motion, even at absolute zero (hence "zero point"), but none of it can be extracted as energy.

Welcome to SFN AFAIK a time crystal is predicated on no energy loss, so you’d destroy it by removing energy from it. Like taking energy out of a pendulum - it would stop ticking. It certainly doesn’t generate any energy.

For reference: https://www.nature.com/articles/s41586-021-04257-w

You don't know anything about it: https://mathshistory.st-andrews.ac.uk/Extras/Einstein_ether/ He later changed his mind.

Since Google physicists created the first time crystal, I've been wondering if this new state of matter could be a source of infinite energy. Could a machine be built that can harvest the energy of a time crystal in some form? (I'm in middle school, so I don't have much experience with physics)

Judging by the jumping spider one way to think of a tarantula being less creepy might be to try and focus on either the head or the eyes separately rather than simultaneously in order to avoid multitasking the reflection of the eyes with the slight neurological complexity of their brain. Viewing their retina as a concave lens might imply that the tarantula is mostly neurological whereas viewing their retina as a concave mirror might make the creature appear more transparent and photonic. The eyes are often hidden in smaller spiders such that it’s easier to view the creatures as neurological without the need to view their retina as a lens where the retina might be as small as a concave mirror. In other words if you’re afraid then you could dilute the creature as being deterministic and neurological or as being thoughtless and visual. The way the jumping spider’s eyes are black might imply that their vision is tinted darker or black.

This evening when I get home I will be able to run the formulas for you. Yes you can calculate the vacuum energy density per cubic metre. For that one can get a decent estimate using the critical density formula. (Assuming Lambda is the result of the Higfs field) one line of research. The calculations differ for the quantum harmonic oscillator contributions however that results in the vacuum catastrophe but I also have the related calculations for that as well.

As light climbs in and out of a gravity well it will blue shift or redshift. For example an outside observer looking at infalling material at the EH of a blackhole will see infinite redshift but an observer at the EH will see infinite blue shift. This is due to gravitational redshift The path will be determined by the Principle of least action which correlates the Potential energy and kinetic energy terms. What most ppl don't realize is that the path is never truly straight. That's just the mean average. If you consider all the little infinitesimal changes in direction (sometimes up/down left right etc) then it becomes much easier to understand. As Markus the geodesic equations are the extremum of all the miniscule deviations

Hi, The average vacuum energy is estimated to about 3 GeV/m^3 (the observed). If relying on this value (when the calculated in extremely much higher). -And the Higgs field energy VEV, the vacuum expectation value, is both observed in the LHC experiment and fairly calculated to about 246 GeV. How are these differences explained in QM physics? 3 GeV versus 246 GeV? I understand that the VEV amount is presented without any special volume in mind. But surely the VEV isn't correlated to the cubic meter volume, though must be estimated to the Planck scale. Far minor than the m^3 which the vacuum is given with. The VEV is a universal constant thought to fill all universe with neither any much higher nor any lower energy content. This issue is raised with the condition of both the vacuum energy volume and the Higgs field are without any elementary particles, though being absolutely empty of any visible "matter". -Without even one single photon or neutrino or whatever. The only content is the absolute vacuum itself (3 GeV). The VEV can be regarded for proven with the Higgs boson discovery in 2012. And the vacuum content have with the Planck Collaboration project also been verified. /chron44

Fiber optic cables operate on the principle of total internal reflection, not the photoelectric effect.