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Monster gravitational waves spotted for first time

nature.com

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Re: Monster gravitational waves spotted for first time

#171

Post by urinotherapist »

AdamH12113 wrote: post #115
urinotherapist wrote: post #111

Earlier quoted context omitted.

If two people are in parallel, they will make two parallel circles. If two people aimed at a singe point, they are not in parallel. Space-time is 4d array: array of framebuffers. You can stretch your mathematical model all day long, but you knowledge must be mapped to reality somehow. In model we have space-time, while in real world we have "physical vaccum" ("something nothing" or "phaccuum", for short). I prefer to…

> If two people are in parallel, they will make two parallel circles. If two people aimed at a singe point, they are not in parallel. In spherical geometry, the equivalent of a straight line is a great circle. There are no parallel great circles. That's why I used the phrase "initially parallel" -- at the starting point, both people's paths are at a 90-degree angle to the great circle connecting their locations. I di…

> In spherical geometry, the equivalent of a straight line is a great circle.

Yes, of course. If we substitute parallel lines with straight lines in spherical geometry and mix 2D and 3D spaces, then our mental model will be nonsensical but cute.

We found no evidence of fourth dimension in the real world, so we cannot map this cute mathemagical model to reality.

Re: Monster gravitational waves spotted for first time

#172

Post by MAGZine »

xattt wrote: post #122
jessriedel wrote: post #53

Earlier quoted context omitted.

Yes, that's basically right. The gravitational way has a direction (say, z) in which its propagating. Within the plane perpendicular to that direction (x-y), a circular ring of particles will at at one moment experience squeezing in one direction (x) and stretching the perpendicular direction (y). As the wave passes through and you move from the peak of the wave to the trough, the directions reverse, so the first dir…

> Just as a child can swing their legs at the resonant frequency of a swing to pump up their sinusoidal amplitude, a very weak gravitational wave can pump up a ring oscillator if it's oscillating at the ring's resonant frequency. So is it possible that a passing gravitational wave could initiate some natural process that otherwise might have not happened?

I don't see it as impossible... Cosmic events frequently give rise to events that might not otherwise happen.

The real question is, is the change meaningful? If you have a tsunami but it doesn't change anything meaningful, is it an interesting observation outside of the event itself?

Re: Monster gravitational waves spotted for first time

#173

Post by User23 »

adgjlsfhk1 wrote: post #127
ben_w wrote: post #113

Earlier quoted context omitted.

Light does slow in a medium, the statement presumes the light is in a vacuum. From the point of view of the photon, "forwards" is, like time, a null[0] dimension. [0] I may be using that word imprecisely, but I can't think of a better one.

This isn't quite true. At a macro level, light slows down. At a micro level, photons travel at the speed of light, get absorbed and re-emitted, and change directions. These effects average out to looking like photons traveling slower.

At the micro level there are infinitely many paths the photon follows and most of them involve it traveling considerably faster than the speed of light. While they cancel out, if you omit them then the calculations don’t give correct results, so they’re happening inasmuch as anything can be said to happen scientifically. If you want to object that that contradicts GR well there is a Nobel prize or ten waiting for whoever squares that circle.

Re: Monster gravitational waves spotted for first time

#175

Post by urinotherapist »

MichaelMoser123 wrote: post #161
mtlmtlmtlmtl wrote: post #151

Modern physics(and engineering) is kind of absurd. And I mean that in a good way. LIGO? I didn't believe at all that it would ever work. Even when they got detections I kinda thought they were chasing their own tails. Now the evidence is pretty much rock solid that the data is real(multiple facilities, correlations with light observations for neutron star mergers, etc). Then I heard about LISA, which essentially is b…

so how comes they can't get this fusion thing to work?

Fussion is easy, hyndrogen nukes were detonated decades ago. Ask them about LENR (Low Energy or Lattice Enabled Nuclear Reactor). Cold Fusion topic is reputation-damaging for scientists for decades. I banned multiple times here for "participation in discussion". Now, LENR is used to boost fusors performance by two order of magnitude (for medical purpose).

Re: Monster gravitational waves spotted for first time

#176

Post by posterboy »

olddustytrail wrote: post #99
dangond wrote: post #86

Earlier quoted context omitted.

Out of curiosity, from someone who has never worked with non-euclidean geometry, what does it mean for a path to be curved in non-Euclidean space? My outsider understanding of curvature is that the inside of a curve is shorter than the outside of the curve, whereas a line has the same length on either side (assuming we give these curves and lines some thickness). But, if the shortest path can be curved, what do we me…

It's not too complicated. Get a round ball of some sort. When you draw on the surface, that's a "non-Euclidean space". Take a straight line down from the "north pole" of your ball to its equator. Draw another straight line around a quarter of the equator. Draw a third line back to the pole. You've just drawn a triangle with 3 straight lines and the angles add to 270 degrees. A non straight line is just not the shorte…

Calling that a "straight" line with a straight face is so Euclidean. Get over it.

Shortest distance between two points is what it is.

Re: Monster gravitational waves spotted for first time

#177

Post by __MatrixMan__ »

MichaelMoser123 wrote: post #161
mtlmtlmtlmtl wrote: post #151

Modern physics(and engineering) is kind of absurd. And I mean that in a good way. LIGO? I didn't believe at all that it would ever work. Even when they got detections I kinda thought they were chasing their own tails. Now the evidence is pretty much rock solid that the data is real(multiple facilities, correlations with light observations for neutron star mergers, etc). Then I heard about LISA, which essentially is b…

so how comes they can't get this fusion thing to work?

It's only superconducting magnets and 100M degree plasma, how hard could it be?

Re: Monster gravitational waves spotted for first time

#178

Post by JumpCrisscross »

MichaelMoser123 wrote: post #161
mtlmtlmtlmtl wrote: post #151

Modern physics(and engineering) is kind of absurd. And I mean that in a good way. LIGO? I didn't believe at all that it would ever work. Even when they got detections I kinda thought they were chasing their own tails. Now the evidence is pretty much rock solid that the data is real(multiple facilities, correlations with light observations for neutron star mergers, etc). Then I heard about LISA, which essentially is b…

so how comes they can't get this fusion thing to work?

> how comes they can't get this fusion thing to work?

Fusion energy involves conjuring physics which don’t exist in that form in the known universe. (Stellar fusion happens at lower rates than what we’re targeting. The only reason it works is because stars are so huge.)

Re: Monster gravitational waves spotted for first time

#179

Post by JumpCrisscross »

distant_hat wrote: post #169
MichaelMoser123 wrote: post #161

Earlier quoted context omitted.

so how comes they can't get this fusion thing to work?

Fusion is easy and you can set off a hydrogen bomb whenever you like, it is turning that energy into electricity that's the hard part.

> it is turning that energy into electricity that's the hard part

It’s creating a stable, recurring reaction that’s the hard part.

Re: Monster gravitational waves spotted for first time

#180

Post by adrianN »

MichaelMoser123 wrote: post #161
mtlmtlmtlmtl wrote: post #151

Modern physics(and engineering) is kind of absurd. And I mean that in a good way. LIGO? I didn't believe at all that it would ever work. Even when they got detections I kinda thought they were chasing their own tails. Now the evidence is pretty much rock solid that the data is real(multiple facilities, correlations with light observations for neutron star mergers, etc). Then I heard about LISA, which essentially is b…

so how comes they can't get this fusion thing to work?

Nobody wants to pay for it. We have other forms of energy that are cheaper and available right now.
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