Can Light Travel Forever in Space While Baryonic Matter Decreases?

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Discussion Overview

The discussion revolves around the nature of light, its interaction with baryonic matter, and the implications of mass decay in the universe. Participants explore whether light can travel indefinitely in space while baryonic matter decreases over time, touching on concepts from nuclear fusion, photon behavior, and mass-energy equivalence.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that stars emit light by converting rest-mass energy into light energy, referencing the equation E = mc².
  • Others argue that while total mass decreases over time, the number of baryons remains constant, with some mentioning theories of proton decay that lack experimental verification.
  • There is a claim that the rate of mass decay into radiation exceeds the rate at which that radiation is reabsorbed into matter.
  • One participant emphasizes that most radiation in the universe results from fusion processes, particularly the conversion of hydrogen to helium, which is unlikely to reverse.
  • Another viewpoint suggests that light, as photons, continues until absorbed by matter, highlighting the distinction between light as particles and waves.
  • Some participants discuss the process of photon emission during nuclear fusion in the sun, noting the lengthy time it takes for photons to reach the surface.
  • There is a challenge to the description of how light particles are emitted, with a clarification that photons do not "glow" but have energy that determines their color.
  • One participant questions the mass difference between helium-4 and hydrogen, attributing it to binding energy within the nucleus.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the behavior of light and baryonic matter, with no consensus reached on the implications of mass decay or the nature of light's interaction with matter.

Contextual Notes

Some claims depend on specific definitions of mass and energy, and there are unresolved questions regarding the mechanisms of light emission and absorption.

WCOLtd
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I was thinking about light and baryonic matter.

My understanding is that stars emit light by essentially converting their rest-mass energy into light energy according to the equation E = Mc2.

I wonder though, does light travel into the depths of space forever? (meaning total baryonic matter would decrease with time) or is light soley an interaction between masses?
 
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Total mass does decrease with time, although the number of baryons remains the same. For example He4 has slightly less mass than 4 x H1. However there are theories predicting proton decay, but this has never been experimentally verified.
 
so the rate at which mass decays into radiation is greater than the rate at which decayed radiation is re-absorbed into matter.
 
WCOLtd said:
so the rate at which mass decays into radiation is greater than the rate at which decayed radiation is re-absorbed into matter.
I am not sure what you are trying to get at. Essentially almost all of the radiation in the universe (stars) results from fusion processes - the most important being 4 H1 to He4. These processes are extreemly unlikely to reverse.

As a result the radiation spreads throughout the universe, including keeping life on earth. Some of it gets reabsorbed by matter in CHEMICAL reactions, not nuclear. Most of it just keeps going and heating things up.
 
well think of light as photons and waves. Light will go on until it is absorbed by some form of matter.
 
i think light is a photon particle which is emited out of the sun in a nuclear fussion of the hydrogen and helium atoms in the sun
when these to highly charged atoms collide they release a higly charged proton this proton thravels in intense speed which emits light particles
i honestly don't know how those particles glow
please answer :)
 
varun19 said:
i think light is a photon particle which is emited out of the sun in a nuclear fussion of the hydrogen and helium atoms in the sun
when these to highly charged atoms collide they release a higly charged proton this proton thravels in intense speed which emits light particles
i honestly don't know how those particles glow
please answer :)

Photons emitted by the fusion process are not in the visible light energy range. They only very slowly work their way out to the photosphere. The number I recall is something like 10,000 yrs for a photon created in the center of the sun to find its way out to the suns surface. The visible light we receive is emitted by the photosphere which comprise only the very outer most layers of the sun.

Photons do not "glow". Each one has an energy, which we perceive as color, that is determined by the source of the photon.

these to highly charged atoms collide they release a highly charged proton this proton travels in intense speed which emits light particles

To the best of my knowledge this is not a valid description.
 
Integral said:
The number I recall is something like 10,000 yrs for a photon created in the center of the sun to find its way out to the suns surface.

I seem to remember something on the order of 100,000 yrs. Still, ridiculously long!
 
varun19 said:
a higly charged proton this proton thravels in intense speed which emits light particles
i honestly don't know how those particles glow

When a charged particle like an electron or proton accelerates or decelerates, it will give off electromagnetic radiation. This is what is done in radio broadcasting. If the electromagnetic radiation has wavelengths between 400 nm to 700 nm, it will be in the visible range, and we call it "light". But often "light" is used as a short hand for all electromagnetic radiation.

http://en.wikipedia.org/wiki/Radio
 
Last edited:
  • #10
He4 has 2protons /2neutons .4xH1=4p.how has he4 got less mass when mass-p<mass-n?
 
  • #11
johnpeel said:
He4 has 2protons /2neutons .4xH1=4p.how has he4 got less mass when mass-p<mass-n?

The difference in mass is the binding energy which holds the He4 nucleus together.
 

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