The dead cores of two stars collided 130 million years ago in a galaxy
somewhat far away.
The collision was so extreme that it caused a wrinkle in space-time — a
gravitational wave. That gravitational wave and the light from the stellar
explosion traveled together across the cosmos. They arrived at Earth
simultaneously at 6:41 a.m. Eastern on August 17.
The event prompted worldwide headlines as the dawn of “multimessenger
astronomy.” Astronomers had waited a generation for this moment. But it was
also the first-ever direct confirmation that gravity travels at the speed of
light.
The Speed of Gravity
We all know light obeys a speed limit — roughly 186,000 miles per second.
Nothing travels faster. But why should gravity travel at the same speed?
That question requires a quick dive into Albert Einstein’s general
relativity, or theory of gravity — the same theory that predicted
gravitational waves a century ago.
Einstein overthrew Isaac Newton’s idea of “absolute time.” Newton thought
time marched onward everywhere at an identical pace — regardless of how we
mortals perceived it. It was unflinching. By that line of thinking, one
second on Earth is one second near a black hole (which he didn’t know
existed).
Newton also thought gravity acted instantaneously. Distance didn’t matter.
It’s All Relative
But then Einstein showed that time is relative. It changes with speed and in
the presence of gravity. One of the ramifications of that is that you can’t
have simultaneous
actions at a distance. So information of any kind has a finite speed, whether it’s a photon —
the light-carrying particle — or a graviton, which carries the force of
gravity.
“In relativity, there is a ‘speed of information’ — the maximum speed that
you can send information from one point to another,” says University of
Wisconsin-Milwaukee physicist Jolien Creighton, an expert on general
relativity and member of the LIGO team that first spotted gravitational
waves.
Creighton explains that in electromagnetism, when you shake an electron, it
creates a change in the electric field that spreads out at the speed of
light. Gravity works the same way. Shake a mass and the change in the
gravitational field — the gravitational wave — propagates at that same
speed.
“So the fact that the speed of gravitational waves is equal to the speed of
electromagnetic waves is simply because they both travel at the speed of
information,” Creighton says.
There’s an easy way to picture this, too. Imagine the sun vanished right
now. Earth wouldn’t just drift into space instantly. After eight minutes,
Earth would go dark and simultaneously push off in a straight line.
Quite stupid:
ReplyDelete"“So the fact that the speed of gravitational waves is equal to the speed of electromagnetic waves is simply because they both travel at the speed of information,” Creighton says.
Information must have a speed limit and thus be limited by a time frame, or information/existence would collapse in on itself, and so would gravity. The Big Bang would have been stillborn.
DeleteThen please explain paired particles and faster than light transfer of information betwixt such. :)
ReplyDeleteTHE problem is that physicists give lip service to the existence/implication of non-local space, which is timeless and "distanceless", but then go off on a tangent looking for some model with X number more dimensions to explain it. The EPR paradox shows (proves?) that Planck scale, quantum, entities (photons, electrons quarks...etc.) must exist in local AND non-local space >>>simultaneously<<<. This allows those entities to move, interact and be absorbed in 4-D local space as we have observed them, but also to coordinate their characteristics with their paired entities, instantly, “in” non-local space.
DeleteMost likely, non-local space is, for lack of a better word, the ether or fabric of space, from which local space was ejected in the Big Bang, and in which it is now suspended. This implies that there is a Planck scale interface or filter between the two which allows sub-Planck scale entities to pass, but not larger ones, like protons. Some experiments have suggested that larger entities such as protons, atoms or molecules, exhibit characteristics of entanglement, but it's more likely just the entanglement of their component quarks, electrons and other Planck scale entities.
BTW, the transfer is more than faster than light, it's instantaneous because, as I said, non-local space is timeless and distanceless, which is to say dimensionless.
Amazing 🤩 I have often wondered about this scenario !
ReplyDeleteCreighton states "you can’t have simultaneous actions at a distance." Yet, Quantum phisics posit the simultaneous action-reaction of two particles in what they call "entanglement." Diesnt this contradict Creighton's statement?
ReplyDeleteAgree. Quantum physics tells us we CAN have simultaneous actions at two opposing- even light year lengths . Creightons statement is contradictory to the laws of Quantum physics.
DeleteWhat is "the speed of information"? Information is already transferred by electromagnetic waves.
ReplyDeleteCan you show me an example which carries information without photons?
THE problem is that physicists give lip service to the existence/implication of non-local space, which is timeless and "distanceless", but then go off on a tangent looking for some model with X number more dimensions to explain it. The EPR paradox shows (proves?) that Planck scale, quantum, entities (photons, electrons quarks...etc.) must exist in local AND non-local space >>>simultaneously<<<. This allows those entities to move, interact and be absorbed in 4-D local space as we have observed them, but also to coordinate their characteristics with their paired entities, instantly, “in” non-local space.
DeleteMost likely, non-local space is the, for lack of a better word, ether, or fabric of space, from which local space was ejected in the Big Bang, and in which it is now suspended. This implies that there is a Planck scale interface or filter between the two which allows sub-Planck scale entities to pass, but not larger ones, like protons. Some experiments have suggested that larger entities such as protons, atoms or molecules, exhibit characteristics of entanglement, but it's more likely just the entanglement of their component quarks, electrons and other Planck scale entities.
Saying that the speed of light and gravitational effects travel at the same speed because that's the speed of information does not convey any new understanding, I belive that we should change the way we look atthe speed of light, look at is more as a fundamental property of the universe instead of just a speed value, its like something was moving and then totally stopped, does that mean the speed 0 can be pushed a little lower? no it stopped, 0 is not a speed anymore its a property
ReplyDeleteSpacetime is viscous. It is not empty. It is expanding, as we know, and forces matter to squish together. That's what gravity is: the scrunching together of matter by the "force" - or pressure - of spacetime.
ReplyDeleteGravity is not a force.
ReplyDeleteThis comment has been removed by the author.
DeleteAlthough lacking a forceful personality Gravity is certainly attractive.
DeleteHow do they know exactly and with certainty that the wave received [gravitational torsion wave] correspond to the explosion of the two dead core of stars 130 millions year ago?
ReplyDelete