19 ms·
The “Oh-My-God Particle”
- zaarn 9y agoTo make it a bit more graspable; A baseball at 90% the speed of light will cause a fairly large nuclear detonation. [0] This particle moved at 99.99999999999999999999951% the speed of light. IIRC from when I worked it out a month ago or so (baseball with that speed), it was in the region of 10^25 J, pretty close the energy the entire sun is outputting each second or a couple million nuclear bombs. (10^25 particles, 4.8 joule per particle) [0]: https://what-if.xkcd.com/1/ https://what-if.xkcd.com/1/
- Parcissons 9y agoIf such a particle interacts with the water of my brain- would i drop dead?
- deleted 9y ago[deleted]
- icebraining 9y agohttps://www.reddit.com/r/askscience/comments/7dqqsh/what_would_happen_if_you_were_hit_by_the_ohmygod/ https://www.reddit.com/r/askscience/comments/7dqqsh/what_wou... https://www.reddit.com/r/askscience/comments/3o16ut/what_would_happen_if_the_ohmygod_particle_had_its/ https://www.reddit.com/r/askscience/comments/3o16ut/what_wou...
- zaarn 9y agoIf such a baseball would interact with your brain, then yes. That would be kill. If only the particle interacted: no. It's too fast to reasonably interact with something as short as going through a human body with any meaningful amount of energy.
- madeuptempacct 9y agoET talking to us. Or not. How far away is the "origin hot spot"? What's the current theory on source?
- bitwize 9y agoSo did the detector get clobbered by this particle?
- al2o3cr 9y agoThe detector used doesn't interact directly with the particle - it observes the light emitted as the particle (& the subsequent shower) interacts with the atmosphere.
- madaxe_again 9y agoThey're called Air Showers - https://en.m.wikipedia.org/wiki/Air_shower_(physics) https://en.m.wikipedia.org/wiki/Air_shower_(physics)
- Nicksil 9y agoNon-mobile link: https://en.wikipedia.org/wiki/Air_shower_(physics) https://en.wikipedia.org/wiki/Air_shower_(physics)
- smueller1234 9y agoTo nitpick: this is only mostly correct. The predominant detection method is actually having arrays of particle detectors on the ground that register through going particles. Because you have an array of them, you can use detection timings of a number of triggered detectors to compute arrival detection/etc. These more "indirect" detectors get a 10x data collection advantage over fluorescence telescopes because they run 24x7 whereas the telescopes run in clear, moonless nights. (The moon in the field of view can actually burn out the camera.) Source: subject of my thesis was trying to calibrate the energy measurement of the fluorescence telescopes by using models of the air shower profile and relative light yield from fluorescence vs Cherenkov effects to infer a scalar fluorescence light yield parameter.
- stephengillie 9y agoHiRes utilized the atmospheric fluorescence technique that was pioneered by the Utah group first in tests at the Volcano Ranch experiment and then with the original Fly's Eye experiment. [0] The cosmic ray hits a molecule in Earth's atmosphere, which causes it to ionize. When it regains electrons, they emit UV light, and the detector catches this while scanning the sky. [1] [0] https://en.wikipedia.org/wiki/High_Resolution_Fly%27s_Eye_Cosmic_Ray_Detector https://en.wikipedia.org/wiki/High_Resolution_Fly%27s_Eye_Co... [1] http://www.telescopearray.org/index.php/history/history-of-the-air-fluorescence-technique?showall=1; http://www.telescopearray.org/index.php/history/history-of-t...
- Jun8 9y agoNot on this particle but relevant if you're interested in cosmic particles: For my son's 5th grade Science Fair project we are building a cloud chamber to detect cosmic particles! As crazy as that sounds we've decided on this project after watching videos showing how ridiculously easy it is to build one, e.g. see this one: https://www.youtube.com/watch?v=pewTySxfTQk https://www.youtube.com/watch?v=pewTySxfTQk. Most designs call for dry ice (cheap, ~$10 for 10 lbs but may be hard to find a local store) but you can also build one using an air duster: https://www.youtube.com/watch?v=QCAVlMTBMe0 https://www.youtube.com/watch?v=QCAVlMTBMe0! Fun fact that I've learned from him during research: humans are exposed to cosmic radiation which is on average equivalent to 10 chest x-rays per year. It would be interesting to look at the impact of this on, e.g. cancer rates among people living at sea level versus cities with high elevation, e.g. Quito in Ecuador.
- Varcht 9y agoVolume/time - pour slowly into a funnel and it works, pour too fast the funnel overflows and you get cancer. People accustomed to high altitudes likely have bigger funnels.
- IntronExon 9y agoWhat isn’t known about the relationship between exposure regimes and poor outcomes could fill the complete OED. Is it really a hormesis model? Linear No Threshold? Linear? Supra-linear? Linear-quadratic? We don’t know, and generally speaking it would be unethical to try and find out using humans.
- itp 9y agoIt would be interesting to look at the impact of this on, e.g. cancer rates among people living at sea level versus cities with high elevation, e.g. Quito in Ecuador. It is interesting, and there are some studies exploring this and related issues. The results are not always immediately intuitive! https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4113517/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4113517/ is one good place to start.
- jamesash 9y ago
- vectorEQ 9y agothis particle physics is just silly and it will never lead to anything but more tiny and faster particles which do inexplicable things. such useful science ... really... Here's something actually interesting >.> but no one care about it.... http://aip.scitation.org/doi/abs/10.1063/1.2423240 http://aip.scitation.org/doi/abs/10.1063/1.2423240
- staplers 9y agoand it will never lead to anything Which particle physicist hurt you?
- deleted 9y ago[deleted]
- zaroth 9y agoWell they are certainly very good at building big honking machines with our tax dollars! :-)
- ppaattrriicckk 9y agoWithout being an expert on the subject, I hope some of what is learned from the engineering of those big honking machines might be relevant for attempts at sustainable fusion. Plus: https://en.wikipedia.org/wiki/Particle_physics#Practical_applications https://en.wikipedia.org/wiki/Particle_physics#Practical_app...
- saagarjha 9y agoWell, we know no other way of building them other than by making big honking machines. It's similar to spaceflight; are you against this as well?
- saagarjha 9y ago> this particle physics is just silly and it will never lead to anything but more tiny and faster particles which do inexplicable things. Wikipedia has a section on the practical applications of particle physics: https://en.wikipedia.org/wiki/Particle_physics#Practical_applications https://en.wikipedia.org/wiki/Particle_physics#Practical_app....
- neor 9y ago"In the particle's reference frame, the photon would move away from it at the speed of light." For some reason I've never been able to wrap my head around this. Anyone know a good explanation for this stuff?
- maze-le 9y agoMe neither, but I always had the idea, that it is impossible to think about events, at a velocity of c, since it is impossible to properly think about 2 events, that are infinitely separated in time. The Lorenz-Factor(γ) for a velovity approaching c approaches infinity. Thus, from the reference frame of a particle at c, the time dialation: ΔT = γ*Δt, also becomes infinite. 2 ticks on a clock (Δt) of an ordinary observer, take an infinite amout of time in the reference frame (ΔT). This doesn't prove or explain anything, but the fact that we can't handle infinities very well, in our casual thinking.
- posterboy 9y agoNo no no, what we can't handle is objectivity! Everything is relative so it is striking me as absolutely paradox to pretend we could leave our frame of reference anyway and "ride a photon" measuring it's speed with a stop watch. Instead you simply have to deal with towers of abstractions, understand the experiments. It is counter-intuitive to claim we also couldn't see photons, but really, the disconnect between theory and phenomenology is rather large. I guess we are only really interested in the weak-electromagnetic force. And that's a probabilistic theory thanks to quantum mechanics. Discrete systems are macroscopic simplifications for didactic and deductive reasons. Gravity is next to the other three basic forces. That's a simple dualism. So time stands still for the photon, but space bends. And we can't fully explain how. And don't get me started on infinity. It's just a number big enough for all intents and purposes. Conversely, it's pretty simple to think about the opposite: Nothing. So if you you take an infinite amount of time to observe a clock at light speed from your inertial frame of reference, it will just not move at all -- there are no "2 ticks". Corollary: A photon doesn't experience time at all. And this holds in quantum mechanics, because a photon doesn't exist until observed. A photon is thus the measure of interaction, a delta on our clock. Colloquially, time is the order of events -- if nothing happens, time stands still. For sake of the argument: If you just switch the photon and observer in your example, the photon in infinite time wouldn't "see" any time pass on the outside observers clock. He wouldn't move. But this is just too simplistic, you have two points in space that practically can't move, because they don't From the frame of reference of a photon, the environment would > 2 ticks on a clock (ΔT) at c, take an infinite amout of time in the reference frame of an ordinary observer (Δt). Extending the thought, you are trying to multiply infinity by infinity. As you said, we cannot handle infinities. I guess that is because there can be only one, one singularity, one universe. That's why the speed of light is set at unit-interval.
- lloeki 9y agoIt's too bad there's no anecdote in the article as to how the particle came to be such named. Compare with the Wow! signal[0] for what I mean. I bet something similar happened. [0]: https://en.wikipedia.org/wiki/Wow!_signal https://en.wikipedia.org/wiki/Wow!_signal
- api 9y agoMy favorite speculation is that it's the jet wash from someone's interstellar antimatter rocket. Unlikely, but fun. :)
- nategri 9y agoHey this is the field I did my PhD in! Some fun facts: * The flux of particles in this energy regime is so low that you get about 1 per square kilometer per century, so studying them necessitates doing really wild stuff like instrumenting a patch of land the size of Rhode Island. See: https://en.wikipedia.org/wiki/Pierre_Auger_Observatory https://en.wikipedia.org/wiki/Pierre_Auger_Observatory * These particles are so energetic that in their frame the nominally low-energy photons that comprise the cosmic microwave background appear as an impenetrable gamma ray wall thats prevents them from traveling more than about 100 million lightyears. This seems like an incredible distance but in astronomical terms this means that whatever is producing them is "nearby." We also know they don't come from our own galaxy because arrival directions don't correlate to the galactic plane. * Current consensus says that these particles probably come from very large and active black holes in the center of certain galaxies. These objects are called active galactic nuclei (AGN).
- yaks_hairbrush 9y agoI want to know more about that gamma-ray wall... - Would the CMB be so energetic (from the proton's frame) as to create electron-positron pairs? - If the particle can't travel more than 100m light-years, what happens to it? Does it slow down? Get destroyed? Is the answer markedly different from our reference frame vs the particle's?
- smueller1234 9y agoThis is what happens: https://en.m.wikipedia.org/wiki/Greisen–Zatsepin–Kuzmin_limit https://en.m.wikipedia.org/wiki/Greisen–Zatsepin–Kuzmin_limi... To the second question: it loses energy due to pair creation (iirc, surely simplifying due to bad memory).
- legohead 9y agoWhat would happen if this particle hit a person?
- deleted 9y ago[deleted]
- olskool 9y agoInterested to know what the kinetic energy of a near Planck particle would be.
- dropspace 9y agoSo we don't know what particle this is? Do we know that it's not any of the particles we already know about? As in, is it a new kind of particle, for sure? Or is it just an energised photon or something?