[guest47899]

If Gravity is a mass dependent field, how do Gravity waves propagate w/o dissipating?

[Kryptid]

They do dissipate in a sense: they become weaker the further they travel from their source in the same way that light becomes dimmer the further out you go from a light bulb.

[guest47899]

Gamma waves from the same event that produced the Gravity wave precede Gravity waves by mere seconds. Gravity waves are said to produce a space/time distortions. Why then are Gamma waves not diminished, when Gravity waves following directly behind a Gamma wave by mere seconds are claimed to have diminished?

[Janus]

Gamma waves from the same event that produced the Gravity wave precede Gravity waves by mere seconds. Gravity waves are said to produce a space/time distortions. Why then are Gamma waves not diminished, when Gravity waves following directly behind a Gamma wave by mere seconds are claimed to have diminished?

The gamma waves diminished at the same rate as the gravitational waves did, by the square of the distance. What makes you think they didn't? 

[guest47899]

Gamma waves from the same event that produced the Gravity wave precede Gravity waves by mere seconds. Gravity waves are said to produce a space/time distortions. Why then are Gamma waves not diminished, when Gravity waves following directly behind a Gamma wave by mere seconds are claimed to have diminished?

They are gamma rays, not gamma waves, and they are diminished with distance: If you're twice as far from the source of them, you measure 1/4th as many of them.
The gravity waves precede the gamma rays by a few seconds, not the other way around.
Both travel at light, but the gravity waves are generated before the merger event (like two neutron stars colliding), and the gamma rays during the collision.  Also, the gamma rays are light, and might be slowed by traveling through the non-vacuum of the space between.

excuse getting the arrival sequence backwards. my bad, the question still remains unanswered


en.wikipedia.org/wiki/Electromagnetic_radiation
in homogeneous, isotropic media, electromagnetic radiation is a transverse wave,

hubblesite.org/reference_desk/faq/answer.php.id=42&cat=galaxies
During its journey, the light is "stretched" due to the expansion of space. As a result, much of the light from the most distant galaxies is no longer visible, but has been shifted to the infrared where present instruments are less sensitive.

[guest47899]

so gamma being EM light travels in a wave. as it travels through space/time it elongates. this elongations, reduces its frequency to a lower frequencies of light. yet we have gravity waves arriving seconds before a gamma waves. the gamma waves have not been reduced in frequency  and yet the gravity waves that arrive at basically the same time over millions of light years are claimed to be diminished? 

[Kryptid]

the gamma waves have not been reduced in frequency

According to who?

[Janus]

so gamma being EM light travels in a wave. as it travels through space/time it elongates. this elongations, reduces its frequency to a lower frequencies of light. yet we have gravity waves arriving seconds before a gamma waves. the gamma waves have not been reduced in frequency  and yet the gravity waves that arrive at basically the same time over millions of light years are claimed to be diminished? 

I fail to see what Gravity waves from an event arriving at almost the same time as the gamma rays has to with the shift in frequency due to cosmological red-shift. 
And in either case, the original Black hole collision detected by LIGO was only 1.8 billion light years away,  The red shift at that distance is ~0.88  ( a signal would be measured at ~88% of its original frequency.)  Gamma rays extend over several octaves ( a octave representing a doubling of frequency),  So a gamma ray reduced to 88% of it original frequency could still easily be in the gamma ray range upon detection. 
and while I did read of a gamma ray burst that could be associated with this detection, it isn't 100% verified.  There was a detection of a collision between two neutron stars for which a GRB is associated, but this event occurred only 130 million ly away, and thus would be subject to even a smaller cosmological red shift.

[evan_au]

The gamma waves diminished at the same rate as the gravitational waves did, by the square of the distance. What makes you think they didn't?

My understanding is:
- The intensity of light (power per square meter) reduces as the square of distance. However, the electric field strength reduces proportionally to distance. Our telescopes detect power and thus follow an inverse-square law (or more accurately, they detect the signal to noise ratio, which is a ratio of powers).
- Similarly, the intensity of gravitational waves (power per square meter) reduces as the square of distance. However, the strain (stretch of the light path in LIGO) reduces proportionally to distance. LIGO detects strain and thus follows an inverse- distance law.
- This means that to see twice as far, you have to make an optical telescope 4x more sensitive. But you only have to make LIGO 2x more sensitive.

The magnitude of this effect decreases in proportion to the inverse distance from the source.

See: https://en.wikipedia.org/wiki/Gravitational_wave#Introduction

neutrinos outrunning photons from a supernova, arriving seconds before the light.  This is largely due to the refractive index of the non-empty space surrounding the supernova, something to which the neutrinos are fairly immune.

The difference in detection time between neutrinos and optical signal could be as much as hours - which is the time taken for the mechanical shockwave of the star's core implosion to propagate outwards to reach the star's surface. The neutrinos make the same journey at almost the speed of light.

See: https://en.wikipedia.org/wiki/Neutrino#Supernovae

[guest47899]

Nobody has answered the question, if gravity requires mass, what is the mass that holds a gravity wave intact over millions of light years? before answering, consider that science claims that EM light has 0 mass.

researchgate.net/post/Does_EM_waves_have_mass
"The photons are a bunch of waves confined in space and have quantized energy. The energy in a photon is proportional to its frequency and equals hf where h is the Planck constant. ... However the rest mass is zero because electromagnetic waves do not exist at rest."

[Janus]

Nobody has answered the question, if gravity requires mass, what is the mass that holds a gravity wave intact over millions of light years? before answering, consider that science claims that EM light has 0 mass.

Gravitational waves have zero mass as well.  The gravitational waves detected by LIGO have the same relationship to the gravitational force as electromagnetic waves have to electromagnetic forces.  You might as well be asking; "If the Coulomb force requires a charge,  where is the charge that holds a light wave intact?"  The answer is the charge that intiated the electromagnetic wave in the first place.  Electromagnetic waves are "ripples" in an electromagnetic field.  Gravitational waves are likewise "ripples" in a gravitational field.  Since both electromagnetic and gravitational fields are infinite in extent, So would be the propagation of these ripples.

It is a bit disingenuous to claim that no one has answered this question when this is the first time you've actually asked this question.   Your previous questions never indicated that this is what you were thinking.  We can't read your mind to see the question behind the question. Especially if that question appears to be based on your own personal interpretation of something.

researchgate.net/post/Does_EM_waves_have_mass
"The photons are a bunch of waves confined in space and have quantized energy. The energy in a photon is proportional to its frequency and equals hf where h is the Planck constant. ... However the rest mass is zero because electromagnetic waves do not exist at rest."

[yor_on]

If you think of gravity as a net, then put this net into three dimensions covering everything. Then a 'gravity wave' will be something shaking this net, and as the 'shake' propagate in the fourth dimension which is 'time' it will move relative its source. As Kryptid write it will be a hell of a lot stronger at its source (someone shaking it) than it will be at Earth.

[guest47899]

So, if both the gravity wave and the gamma wave have zero mass and both are traveling at the speed of light, then by the law of conservation, their energy is invariant. So, the gravity wave arrives first followed 1.7ms behind by a gamma wave from over 1.3 billion light years. Again, traveling at the speed of light, zero mass loses no energy, its frequency is reduced but it's energy is invariant. The gravity wave in front of the gamma wave is also invariant but it has no reduction in frequency as it is not an EM force. The gravity wave therefore is monolithic. So, what holds a gravity wave intact at the speed of light where no mass exist?  The only other variable in this equation is the EM Gamma wave energy. For E=Mc2,  Mass is interchangeable with Energy, this means baryon mass alone is not needed to  foster gravity. The Gamma wave in this case is essential to maintain the integrity of the gravitational wave.

In other cases where the gravity wave is produced by a black hole merger where light is not involved, does the gravity wave with zero mass also act accordantly or does the properties of the gravity wave alter from it's gamma/gravity wave counterpart significantly?

 

[evan_au]

So, the gravity wave arrives first followed 1.7ms behind by a gamma wave from over 1.3 billion light years.

At this point in time, only one event has been published with a simultaneous gamma ray & gravitational wave detection: GW170817.
- The gamma ray burst was detected 1.7s after the end of the gravitational wave signal (not 1.7ms). A gap of 1.7ms would be caused by the speed of light between the detectors on and orbiting the Earth; 1.7s suggests that a different effect is at play.
- This event was estimated at 130 million light years away (not 1.3 billion light years)

The gravitational waves were observed for about 100s before the merger, as the neutron stars get closer, they orbit more quickly, producing a rapidly increasing frequency "chirp". The endpoint of the signal represents the merger event, where it stops producing gravitational waves.

The gamma rays are due to radioactive decay as neutron-rich material sprays into space, most of which would decay in microseconds or milliseconds. However, the intensity as seen on Earth depends on the area of the source, as seen from Earth. This area starts off as under 10km, but material is sprayed out at a good percentage of the speed of light, so the emitting diameter increases to perhaps ten thousand km in the first 2 seconds, greatly increasing the intensity, as seen from Earth. The diameter expands by another ten thousand km in the next 2 seconds, counterbalanced by the reducing gamma ray emissions of the debris.

So it is possible that the 1.7s delay may be due to the sensitivity of the detector, which could only pick up the signal once the emitting area had expanded by 6 orders of magnitude.

Optical astronomers could pick up the light curve in visible light for 2-3 weeks afterwards; this is powered by decay of isotopes with longer half-lives (like gold and cobalt)
See: https://en.wikipedia.org/wiki/GW170817

[yor_on]

" The gravity wave therefore is monolithic" = *Characterized by massiveness and rigidity and total uniformity'

I f*ng hate when people try to make it more complicated than it is. Where did you get that from?
It's not EM