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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

#141

Post by mpalczewski »

sam_goody wrote: post #139

Can someone please ELI5: I was taught that all items fall at the same speed, due to the gravitational constant. With these waves, does that mean that items will fall at ever so slightly differing speeds, as depending on the size of the wave there is a pull in the other direction, and the constant is slightly off? And OT, but related: Since every item has a gravitational pull related to its mass, would a bigger item f…

Gravitational waves warp space/time. so the distance between two points will be slightly longer/shorter.

Re: Monster gravitational waves spotted for first time

#142

Post by [deleted] »

mpalczewski wrote: post #141
sam_goody wrote: post #139

Can someone please ELI5: I was taught that all items fall at the same speed, due to the gravitational constant. With these waves, does that mean that items will fall at ever so slightly differing speeds, as depending on the size of the wave there is a pull in the other direction, and the constant is slightly off? And OT, but related: Since every item has a gravitational pull related to its mass, would a bigger item f…

Gravitational waves warp space/time. so the distance between two points will be slightly longer/shorter.

[deleted]

Re: Monster gravitational waves spotted for first time

#143

Post by stouset »

taeric wrote: post #138
zeven7 wrote: post #136

Earlier quoted context omitted.

These gravity waves aren't strong enough to pull us off Earth. Everything on Earth is already subjected to gravity, and it doesn't cause nuclear reactions. Gravity waves won't cause impossible configurations to become possible.

Could it impact orbits? Or tides?

I think you are overestimating the amount of power in these gravitational waves by several dozen orders of magnitude.

To even detect these, we need to observe multiple pulsars over long periods of time in order to find minute effects only visible at galactic scales due to the nanohertz frequency of these waves. In other words, spacetime is being stretched and compressed at subatomic scales on a sinusoidal wave with a period of a month or so.

It’s a bit like asking if cosmic rays from the Pinwheel Galaxy are affecting cancer rates.

Re: Monster gravitational waves spotted for first time

#144

Post by charlieflowers »

taeric wrote: post #138
zeven7 wrote: post #136

Earlier quoted context omitted.

These gravity waves aren't strong enough to pull us off Earth. Everything on Earth is already subjected to gravity, and it doesn't cause nuclear reactions. Gravity waves won't cause impossible configurations to become possible.

Could it impact orbits? Or tides?

Or the flip of a coin?

I don’t know the answer but it’s an interesting question

Re: Monster gravitational waves spotted for first time

#145

Post by xattt »

stouset wrote: post #143
taeric wrote: post #138

Earlier quoted context omitted.

Could it impact orbits? Or tides?

I think you are overestimating the amount of power in these gravitational waves by several dozen orders of magnitude. To even detect these, we need to observe multiple pulsars over long periods of time in order to find minute effects only visible at galactic scales due to the nanohertz frequency of these waves. In other words, spacetime is being stretched and compressed at subatomic scales on a sinusoidal wave with a…

> It’s a bit like asking if cosmic rays from the Pinwheel Galaxy are affecting cancer rates.

Thank you for that context!

Re: Monster gravitational waves spotted for first time

#146

Post by pdonis »

sam_goody wrote: post #139

Can someone please ELI5: I was taught that all items fall at the same speed, due to the gravitational constant. With these waves, does that mean that items will fall at ever so slightly differing speeds, as depending on the size of the wave there is a pull in the other direction, and the constant is slightly off? And OT, but related: Since every item has a gravitational pull related to its mass, would a bigger item f…

No, gravitational waves do not affect the equivalence principle and do not change the gravitational constant. They are waves of change in the geometry of spacetime; freely falling objects show these spacetime geometry changes by changes in their relative motion.

Re: Monster gravitational waves spotted for first time

#147

Post by Lichtso »

sam_goody wrote: post #139

Can someone please ELI5: I was taught that all items fall at the same speed, due to the gravitational constant. With these waves, does that mean that items will fall at ever so slightly differing speeds, as depending on the size of the wave there is a pull in the other direction, and the constant is slightly off? And OT, but related: Since every item has a gravitational pull related to its mass, would a bigger item f…

Well in both your questions it depends on how you define speed. It is commonly understood to be the first derivative of position, or the quotient of distance divided by a time-span. But how do you define and measure distance and time-spans? Which reference frame do you use?

Also, the things falling in a vacuum at the same speed thing is a common misconception. The two arguments usually are that the mass of one body can be canceled out in both equations or that splitting a body into two won't make its halves fall slower.

To answer the question: Given all bodies have the same size, a constant distance to and mass of the reference body (usually earth) and everything starting at rest with no relative speed heavy and light bodies do experience the same acceleration, but a heavy body will collide sooner than a light body. Did it "fall faster"?

Re: Monster gravitational waves spotted for first time

#148

Post by derefr »

cyberax wrote: post #83
derefr wrote: post #61

Earlier quoted context omitted.

Acoustic waves propagate through what are essentially elastic deformations of the material they travel through. Can gravitational waves be thought of as propagating by elastically deforming spacetime? If this analogy holds, then can it be taken further? Acoustic waves dissipate their energy insofar as they trigger plastic deformation in a material. Could gravitational waves plastically deform... spacetime itself? Or…

> Or is gravitational energy not dissipated into other forms of energy at all? Extremely weakly. The mechanism is similar to acoustic waves, but the coupling constant is so small, that the amount of dissipated power would be insignificantly small. In theory, you can use gravitational waves to extract energy. For example, you can wait for the "compression" part of the wave, and push a cart uphill during it. Then let i…

Could there exist a material that resistively dissipates gravitational flux more strongly than normally, in the same sense that ferromagnetic materials resistively dissipate magnetic flux more strongly than normally? Something something "gravitational permeability"?

(I guess such a material would interact with gravitational waves as if it had more mass than it does, without that affecting its inertial mass?)

Re: Monster gravitational waves spotted for first time

#149

Post by berniedurfee »

derefr wrote: post #31

What do these waves look like as they pass through us? Acoustic-like compression and expansion of particles as molecules temporarily reorient toward a “down” that is ever-so-slightly off from the Center of mass of the Earth? Also, I assume that these waves are very gentle sinusoids? Could the opposite — a high-amplitude gravitational square wave — be possible? What would it do to the things it passes through?

I was wondering if these waves could affect our brains, even subtly. Maybe cause a reaction in one part of one cell that tips the balance between a neuron firing or not.

Re: Monster gravitational waves spotted for first time

#150

Post by nomel »

sslayer wrote: post #109
ComputerGuru wrote: post #2

More reporting, for a more pedestrian overview: In a major discovery, scientists say space-time churns like a choppy sea https://www.washingtonpost.com/science/2023/06/28/gravitatio... (Archived: https://archive.is/AmRvg )

Imagine if we could take advantage of the time-space potential/differences between gravitational areas to "skip" large parts of space. We would have to have a very precise gravity map, but could also get huge gravity potential boost!

Could we? Is there math that supports this? Wouldn't this require taking some, and then not losing it when the wave passes? I don't see much happening with the earth, as it's experiencing them, so I assume the "extraction" process would be significant and unique.
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