Talk:Oh-My-God particle

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Iron Nucleus

I've changed in the beginning most likely a proton into Iron Nucleus, and halfway in the article subatomic particle into Atomic Nucleus; because of this article: the team has found evidence that these highest-energy cosmic rays might be iron nuclei, rather than the protons that make up most cosmic rays. http://www.nature.com/news/2010/100222/full/4631011a.html

Second I also cut out this part because it wasn't a proton:

-- The particle was traveling very close to the speed of light^[1] — assuming the particle was a proton, its speed was only about 1.5 femtometers (quadrillionths of a meter) per second less than the speed of light, translating to a speed of approximately 0.999 999 999 999 999 999 999 9951c. At that speed, in a year-long race between a photon and the particle, the particle would fall behind only 46 nanometers, or 0.15 femtoseconds (1.5×10⁻¹⁶ s); or one centimeter every 220,000 years.^[2]

The speed of the particle, if it was a proton, is so high that it would experience relativistic time dilation by a factor of about 320 billion. At that rate, the particle could have traveled for the entire duration of the universe's existence while experiencing a bit less than sixteen days of subjective time. --

Michel_sharp (talk) 22:31, 21 June 2015 (UTC+01:00)

I don't think one study's claim that some UHE cosmic rays might be iron nuclei is sufficient to warrant a rewrite of the article. Would you consider reverting those changes and adding a note of reference to this article as an alternative hypothesis instead? Bobathon71 (talk) 21:17, 21 June 2015 (UTC)[reply]

Looking at recent reviews such as http://arxiv.org/abs/1101.4256 and http://arxiv.org/abs/1403.2967 it seems that the iron nucleus hypothesis has merit but is far from being established as fact. If the article is to be rewritten as if this cosmic ray is not a proton, note that the calculation in the sentence beginning "The effective energy..." is no longer correct. Bobathon71 (talk) 12:50, 22 June 2015 (UTC)[reply]

References

^ Bird, D. J. (March 1995). "Detection of a cosmic ray with measured energy well beyond the expected spectral cutoff due to cosmic microwave radiation". Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 441, no. 1, p. 144-150. Retrieved February 14, 2014.
^ J. Walker (January 4, 1994). "The Oh-My-God Particle". Fourmilab.

Wait a minute

It is slower by 1.5 fm/s, but would only be behind 0.15 fm after a full year? There is a problem here. Tazerdadog (talk) 04:00, 27 August 2012 (UTC)[reply]

0.15 fs, not 0.15 fm. The bigger problem is the "year-long" race. A year in what frame of reference? Certainly not relative to the particle -- the particle would observe light traveling at the speed of light. I guess it is relative to a staionary observer. -- Schapel (talk) 14:23, 13 November 2012 (UTC)[reply]

The detected kinetic energy was relative to the Detector; or, in other words, the Particle's velocity, v, was relative to the Detector's frame of reference. Suppose the Year Long Race commences as the Photon and the Oh-My-God-Particle whizz past the Detector. On the passage of one year, as reckoned from within the Detector's frame, the Photon and the OMGP will have receded to two different distances from the Detector. Of course it doesn't have to be relative to the Detector. It can be any frame of reference relative to which the OMGP has its characteristic velocity. — Preceding unsigned comment added by 24.223.130.60 (talk) 00:20, 13 May 2014 (UTC)[reply]

So does that mean that if this particle hit you, it would be like getting hit by a baseball going 60mph? You'd like stagger or fall over for no apparent reason? If not, why not? Would you spontaneously human combust? lol :) This particle is the Oh-My-Devil particle. Dkelly1966 (talk) 16:03, 21 June 2013 (UTC)[reply]

What could be the source of this thing? Kortoso (talk) 22:31, 21 October 2014 (UTC)[reply]

One of the sources named is Cygnus X-3 and if it hit's you, you do not feel anything. These particles travel at a large fraction of he speed of light. It needs more time to impart kinetic energy than is available. Compare it to a bullet flying into a bunch of cotton-balls. Kleuske (talk) 12:51, 22 October 2014 (UTC)[reply]

Wait, so it would just pass through you? Hdjensofjfnen (Is something wrong?) 00:21, 23 February 2016 (UTC)[reply]

AFAIK, yes. In fact,you may be hit with high energy cosmic rays on a daily basis, without noticing. Kleuske (talk) 11:33, 23 February 2016 (UTC)[reply]

My understanding is that the Apollo astronauts were aware of vision disturbances believed to be (on balance of probability) low energy cosmic rays. They said little for fear of being medically disqualified. JRPG (talk) 17:12, 1 March 2017 (UTC)[reply]

Planck Energy

There wasn't a source for the fraction of the Planck energy: 3×10²⁰/1.22×10²⁸=2.46×10⁸. Both Plank Energy and the energy of the particle in question are well sourced. Expressing that as a fraction is a routine calculation. I haven't reverted since a) i'm not that sure how meaningful such a fraction is and b) WP:CALC seems to refer to original research. Any opinions? Kleuske (talk) 09:24, 30 July 2014 (UTC)[reply]

Currently (April 2024) the link to Planck energy doesn't actually shows a definition of Planck energy. Rps (talk) 13:28, 18 April 2024 (UTC)[reply]

Doesn't a photon travel X light-years in X years?

" it would take 220,000 years for the photon to gain a 1 centimetre lead, and the particles will have travelled approximately 86,664,000,000,000,000 kilometers, about 9,160.4 light-years. " so wouldn't the particles have traveled about 220000ly?

159.92.27.130 (talk) 00:22, 28 February 2016 (UTC)[reply]

By definition it does. Where the numbers come from is unclear to me, but they obfuscate more than they explain, so I've deleted the claim. Kleuske (talk) 11:47, 28 February 2016 (UTC)[reply]

Well, I added this in. I think that either 1) the online conversion system is incorrect; 2) My calculations are incorrect; or 3) There might be a misunderstanding here. For more comments on this, come to my talk page or Kleuske's. Hdjensofjfnen (U T C) 00:10, 1 March 2016 (UTC)[reply]

Any of the explanations might be correct, I haven't checked, but the numbers don't seem to add up. How did you arrive at "86,664,000,000,000,000 kilometers, about 9,160.4 light-years"? Kleuske (talk) 09:20, 2 March 2016 (UTC)[reply]

I don't remember, actually... I've computated again, and I got 6.97 light years. At this point, it's best to remove this. Hdjensofjfnen (U T C) Why did GAB withdraw? 21:53, 2 March 2016 (UTC)[reply]

What kind of particle was the omg-particle?

Hi. It has been some years since this event, so I thought there might be some consensus or at least qualified guesses at what kind of particle this omg-particle was? I can see from the above, that it has been proposed to be a proton or an iron nucleus. Does anybody know anything?

Whatever the murky truth, I think it is important to include some information about the nature of this particle in the article. RhinoMind (talk) 22:16, 16 November 2017 (UTC)[reply]

There are three different detector groups with different conclusions from their data. An analysis paper in 2014 concluded: "...Since this work is in progress, we simply remark that a light, nearly protonic, composition is in good agreement with the data" [1]. So maybe protons. But the jury is out. Lamontcg (talk) 02:52, 28 February 2018 (UTC)[reply]

Planck energy proton redundancy

Currently, the article says that a proton with a Planck energy would travel "less than 0.00000000000000000000049% of c faster than the Oh-My-God particle". The OMG particle travelled at 99.99999999999999999999951% c. 99.99999999999999999999951% + 0.00000000000000000000049% = 100%. Therefore, this statement is just saying that the OMG particle had less than the Planck energy, and that massive particles can't travel faster than the speed of light. In other words, it's pointless. — Preceding unsigned comment added by 86.134.76.71 (talk) 14:33, 30 May 2018 (UTC)[reply]

Duplicate article should be deleted

Almost all of this article is already in:

https://en.wikipedia.org/wiki/Ultra-high-energy_cosmic_ray

(except for the Planck stuff, which is not particularly relevant IMO).

Keith McClary (talk) 17:22, 9 January 2019 (UTC)[reply]

Collision energy value

An IP editor on June 30 "miscorrected" the collision energy value from ~10**14 eV to ~10**30 eV (the kinetic energy value), presumably not understanding the difference (or reading too quickly to notice.) They also changed the citation, but their own citation also contains the correct collision energy value that they removed from the article. I've changed the value back, but left both citations. User:Glenn Willen (Talk) 15:32, 8 September 2019 (UTC)[reply]

Incoherent analogy with the baseball

The assertion "equivalent to a 142-gram (5 oz) baseball travelling at about 26 m/s" is incoherent, because the relativistic energy that a 142-gram baseball travelling at 26m/s has is 7.966×10³⁴ eV [2], which is greater than the energy of the particle currently shown on the page [(3.2±0.9)×10²⁰ eV, or 51 J]. A 142-gram baseball should travel at a "complex velocity" in order to have the same energy as the particle. The analogy should use a lighter object. 2.154.185.189 (talk) 20:40, 24 May 2020 (UTC)[reply]

The comparison is of their kinetic energies and does not include the energy of the rest mass, the hypothetical baseball has a kinetic energy of 2.996×10²⁰ eV. 174.78.94.226 (talk) 22:15, 15 July 2020 (UTC)[reply]

Baseball

Can we get a comparison with a globally relatable object, such as a tennis ball or something? This comparison doesn't mean much to us 90% of the world who have never held a baseball ball in our hand. 93.138.1.207 (talk) 01:50, 13 October 2020 (UTC)[reply]

The analogy is a bit confusing but I don't think the type of ball matters. You know what a baseball is, don't you?

Highest Energy Particle?

In the first paragraph there is a claim that the OMG particle was the highest energy cosmic ray discovered up to date, but there have been higher energy particles discovered since. What is the energy of these higher energy particles, and where were they discovered? I can't find any info on this, and a lot of articles I've found claim that the OMG particle is still the highest energy one (though they were posted in the early 2000s or 2010s). So what's going on? Has there been a more recent discovery of even higher energy particles?

Farrahanne (talk) 01:31, 21 January 2021 (UTC)[reply]

The second OMG particle

This was on May 27, 2021 at the Amaterasu array in Utah. Whereas the earlier particle was 320 x 10^18 eV, this second particle was 244 x 10^18 eV and like the first one, we have an idea where it came from but we have seen no powerful event that could have spawned it.(45.13.201.96 (talk) 18:15, 25 November 2023 (UTC))[reply]

[1] Bird, D. J. (March 1995). "Detection of a cosmic ray with measured energy well beyond the expected spectral cutoff due to cosmic microwave radiation". Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 441, no. 1, p. 144-150. Retrieved February 14, 2014.

[2] J. Walker (January 4, 1994). "The Oh-My-God Particle". Fourmilab.

[1]

[2]