Timeline for Could light be dark matter?
Current License: CC BY-SA 3.0
26 events
| when toggle format | what | by | license | comment | |
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| Dec 26, 2023 at 8:33 | answer | added | Allure | timeline score: 0 | |
| Oct 21, 2019 at 21:01 | history | protected | Mike G | ||
| Oct 21, 2019 at 20:59 | answer | added | Fernando C. | timeline score: -2 | |
| Jan 15, 2019 at 6:47 | answer | added | EvilSnack | timeline score: 2 | |
| Jun 22, 2017 at 18:52 | comment | added | ProfRob | Light is massless. Full stop. A better way to think about it is that energy contributes to the spatial curvature that is interpreted as the force of gravity. Either way, the current light content of the universe is a negligible source of energy density. | |
| Apr 13, 2017 at 12:59 | history | edited | CommunityBot |
replaced http://astronomy.stackexchange.com/ with https://astronomy.stackexchange.com/
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| Feb 8, 2016 at 21:45 | comment | added | Jonathan | @fractalspawn I agree with your analysis. We don't see the light unless it enters our retinas (or whatever detection device we use). This means there is a tremendous amount of light we do not see. For example, we don't see a laser beam (light in transit), but we see the point where the beam strikes because light bounces off the object and then enters our eyes. | |
| Feb 8, 2016 at 20:42 | comment | added | coblr | This is pretty interesting. Some say, if it were light, we would see it, but would we? We don't see the photons that are coming off the sun, perpendicular to our line of sight. We don't see them as they pass us heading to Jupiter, but yet there they are, reflecting back to us. In a sense we see the effect of light, but not the light it self (like a laser). I always wondered if it was just that instead of admitting the mass of things is more than we thought, we say it has to be something else. | |
| Oct 7, 2014 at 22:13 | vote | accept | Jonathan | ||
| Oct 7, 2014 at 22:11 | vote | accept | Jonathan | ||
| Oct 7, 2014 at 22:13 | |||||
| Oct 6, 2014 at 22:38 | answer | added | eshaya | timeline score: 10 | |
| Aug 5, 2014 at 19:00 | comment | added | HDE 226868♦ | Interesting. One common idea has dark matter being a WIMP (Weakly Interacting Massive Particle). While photons don't seem to interact via the weak nuclear force, I wonder if electroweak unification could give the photon dark matter idea an interesting twist. | |
| Jul 13, 2014 at 8:43 | history | tweeted | twitter.com/#!/StackAstronomy/status/488242182378512384 | ||
| Jul 4, 2014 at 11:30 | vote | accept | Jonathan | ||
| Oct 7, 2014 at 22:11 | |||||
| Jul 3, 2014 at 11:53 | answer | added | Jonathan | timeline score: 3 | |
| Jul 3, 2014 at 11:40 | comment | added | Jonathan | @Py-ser I would like to see how much of dark matter it accounts for, assuming the mass associated with light (m=E/c^2) gravitates just like the equivalent mass in normal matter. | |
| Jul 3, 2014 at 11:38 | comment | added | Jonathan | @AnthonyX It appears the answers and sources to the linked question show that light does gravitate according to the mass it would have by E=mc^2. If this is true, the big question is, is this enough to account for dark matter? | |
| Jul 3, 2014 at 5:53 | comment | added | Py-ser | In this way, you are assuming that light gravitates much more than ordinary matter. | |
| Jul 3, 2014 at 2:12 | comment | added | Anthony X | An interesting question... if you add up all the energy of all the "in transit" photons in the universe (in some definition of "now") and equate it to mass via E=mc^2, is it a meaningful thing to do (does it behave as mass e.g. have gravity), is that mass of any significance, and if so, does it in any way account for the so-called "missing" or dark matter in our universe, even if only partially? | |
| Jul 2, 2014 at 22:37 | answer | added | harogaston | timeline score: 28 | |
| Jul 2, 2014 at 21:32 | answer | added | Archa | timeline score: 5 | |
| Jul 2, 2014 at 14:28 | comment | added | Yashbhatt | Light can be detected and Dark matter cannot be detected. | |
| Jul 2, 2014 at 12:21 | comment | added | Takku | This seems a little far-fetched and I would expect that if there was light, we would see it. Also, I believe that all cosmological models account for the effect of light/photons/radiation. However, this is an extremely interesting correlation or a line of thought that I think I am absolutely in love with. Being not very comfortable discussing details about cosmology myself, I would like to see any answers people have. So, a +1. Also, great thinking, keep it up. This is the kind of creativity that leads to great research. | |
| Jul 2, 2014 at 12:15 | history | edited | Jonathan | CC BY-SA 3.0 |
Added link to other similar question
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| Jul 2, 2014 at 12:08 | history | edited | Jonathan | CC BY-SA 3.0 |
explained "seeing light" better
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| Jul 2, 2014 at 11:56 | history | asked | Jonathan | CC BY-SA 3.0 |