Has physicist's gravity theory solved 'impossible' dark energy riddle?

www.theguardian.com ^ | Sat 25 Jan 2020 06.40 EST | Hannah Devlin Science correspondent

[Red Badger]

Prof Claudia de Rham’s ‘massive gravity’ theory could explain why universe expansion is accelerating

Cosmologists don’t enter their profession to tackle the easy questions, but there is one paradox that has reached staggering proportions.

Since the big bang, the universe has been expanding, but the known laws of physics suggest that the inward tug of gravity should be slowing down this expansion. In reality, though, the universe is ballooning at an accelerating rate.

Scientists have come up with a name – dark energy – for the mysterious agent that is allowing the cosmos to expand so rapidly and which is estimated to account for 70% of the contents of the universe. But ultimately nobody knows what the stuff actually is.

“It’s the big elephant in the room,” says Prof Claudia de Rham, a theoretical physicist at Imperial College. “It’s very frustrating.”

Change could be afoot. De Rham has pioneered a radical theory that could hold the key to why the universe is expanding faster and faster and explain the nature of dark energy. The theory, known as massive gravity, modifies Einstein’s general relativity, positing that the hypothetical particles (gravitons) that mediate the gravitational force themselves have a mass. In Einstein’s version, gravitons are assumed to be massless.

If gravitons have a mass, then gravity is expected to have a weaker influence on very large distance scales, which could explain why the expansion of the universe has not been reined in.

“One possibility is that you may not need to have dark energy – or rather, gravity itself fulfils that role,” says De Rham.

The work marks a breakthrough in a century-long quest to build a working theory of massive gravity....

[HamiltonJay]

Okay, I am no theoretical physicist, but maybe someone here is. and can explain this in a manner simple enough for those of us who are not in their field.

They tell us that 97 or 98% of the “visible” universe, is moving away from us, due to universal expansion (space itself is expanding) faster than the speed of light...

This means if we were to build a space ship that could reach the speed of light, (the theoretical maximum anything can move through space, including light itself) and launch it in the direction of 97% of the galaxies we can see, it could never ever reach them... EVER... in fact, with each passing moment, even though the space craft is moving at the speed of light, the galaxy it is heading toward would be further away from it, than it was the moment before...

So, the question is, if 97% of the “visible” universe is moving away from us, thanks to expansion, at a speed faster than light... how is that we even see them in the first place? Light leaving those galaxies, heading toward us, would be having the same issues as our hypothetical space craft.... it will never reach us.

So is it simply we are seeing light that left them before they were moving away from us faster than the speed of light? and that is the only reason we can see them? And if that’s true, then there likely would he a lot more galaxies that moved over the barrier to beyond light speed expansion from us whose last light reached us, that could, long before humans evolved?

Anyway, lots of questions.. but one more... Will we ever see a new galaxy ever with these realities? IE one born who’s light hasn’t reached us yet, but isn’t expanding away from us faster than the speed of light ?

Anyway, these are the sorts of questions Insomnia sometimes brings...

[PapaBear3625]

Another possibility is that space-time itself is expanding. It allegedly happened in the first second of the “big bang”, why can’t it still be happening?

[Red Badger]

The farthest galaxies we can "see" are extremely Red Shifted so far that they appear only in infrared wavelength. Any farther and we won't see them at all......... 🤓

[Bitman]

I would much rather they answer this...

The estimated age of the universe is just shy of 14 Billion years. The estimated radius of the known universe is approximately 45 Billion light years. If the speed of light is the maximum speed, how could the known universe be 3x bigger that physics allows?

No, I did not just make these numbers up...

[samtheman]

bookmark

[bennowens]

Universe is not expanding. It is only perceived to be due to a defect in the speed of light. Universe is really steady state. There was no Big Bang and there is no dark matter. Simple!

[Red Badger]

I don’t know.
Maybe they used Metric Light Years.
Or Daylight Savings Light Years.
Or Light years were faster back then..................

[PapaBear3625]

https://en.wikipedia.org/wiki/Expansion_of_the_universe

[Vaquero]

If gravitational waves travel at the Speed of light and the universe is expanding at greater than the speed of light (currently accepted) the waves will never reach an edge.

By using Laser Interferometer Gravitational-Wave Observatory (LIGO) we have detected gravitational waves created when two black holes collided over 3 billion years ago.

I don’t know if they were able to determine the speed of those waves.

[satan]

So what’s so hard about putting a graviton on a scale to see how much it weighs?

[DivineMomentsOfTruth]

Not to mention multi-universes.

[stormhill]

Seems to me that explanation would blow a huge hole in the Big Bang theory, because, my understanding was that the Big Bang occurred when the universe collapsed into a very small, tightly compacted mass.

That sounds more like the Big Bust Theory...or, if you prefer, the Marilyn Monroe Theory.

[Captain Rhino]

Not necessarily.

The Big Bang could have happened just once and the Universe is on its way to total cold entropy. Or it may have somehow produced gravitons with these unique properties in just this last recycling of the Universe’s total substance and that may be the event that stops the cycle.

Either way or whatever, we are not going to be around for the answer. (Some wise guy said it was “42,” but I have my doubts.)

Anyway, I’m hungry. Think I’ll have a pastry and some tea.

[Swordmaker]

This physicist and Gravity Driven Universe Cosmologists are looking for answers and are in a tizzy because they refuse to look at an alternative model which posits another modality for what drives the Universe other than gravity which answers all these problems they cannot solve and even predicts many, if not all, of the puzzles they keep encountering as the delve deeper and farther into space.

The Electricmagnetic Driven Universe Driven Universe states that Electromagnetism, a force 39 orders of power stronger than gravity which is also infinite in reach, fulfills the requirements for answering these puzzles. This theory answers precisely many of the scalable phenomena observed in space and the laboratory that are not explicable by using gravity which cannot explain what is observed, even with using such magical creations as dark matter and dark energy have not and cannot be found after decades of searching for them.—Electric/Plasma Universe PING!

Clear Example of a Birkeland Current
"Z" Pinch with Symmetrical Plasmids
seen in Hubble Telescope View of
The Twin Jet Nebula
ELECTRIC/PLASMA UNIVERSE PING!

If you want on or off the Electric Universe/Plasma Ping List, Freepmail me.

[Nabron]

“Dark energy” isn’t just making galaxies fly away from us, it is increasing the amount of space between them. For example, the distance from the tip of your nose to the tip of your finger seems pretty stable, right? It isn’t... The atoms, the electrons, protons, neutrons, quarks.... The distance between them (and their constituent parts) is also expanding, but we don’t notice it. Eventually, the space between electrons and their atomic nuclei will be too far for any interactions to take place.

[dfwgator]

I’m still trying to figure out how many licks it takes to get to the center of a Tootsie Pop (And no, it’s not 3, that owl lied!)

[thoughtomator]

another hotfix patch to an already-falsified theory ain’t going to cut it

[Captain Rhino]

Owls. Not quite as wise as they would have us believe.

[outofsalt]

Gravitons!? This could result in mass hysteria!

[Red Badger]

I don't have the energy for that!..................😱