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Light by light scattering was first observed at SLAC in the mid 90s by experiment E-144. https://physicsworld.com/a/light-is-seen-to-scatter-off-light/ https:/
by mmmBacon 8y ago
Light by light scattering was first observed at SLAC in the mid 90s by experiment E-144.
https://physicsworld.com/a/light-is-seen-to-scatter-off-light/ https://physicsworld.com/a/light-is-seen-to-scatter-off-ligh...
Link to paper from 1997:
Positron Production in Multiphoton Light-by-Light Scattering
(published in Phys. Rev. Lett., Vol. 79, p. 1626 (1997).)
http://www.slac.stanford.edu/exp/e144/ps/positron_slacpub.ps http://www.slac.stanford.edu/exp/e144/ps/positron_slacpub.ps
- SiempreViernes 8y agoI think this mainly centres on just what should count, here[0] is a paper from 1996 about using astrophysical gamma ray sources to detect the effect of the intergalactic background light, which is also photon photon interactions. [0]: http://adsabs.harvard.edu/full/1996ApJ...456..124M http://adsabs.harvard.edu/full/1996ApJ...456..124M
- keyle 8y agoAny potentially practical use?
- not_kurt_godel 8y agoPurely speculating as a physics-interested layperson, but I imagine this probably either changes or confirms/enhances confidence of various cosmological observations where photon-photon interaction might play a role. For example, maybe certain parameters/characteristics of the CMB have uncertainties potentially related to this phenomenon which can now be tightened up, which could have ramifications for inflation theory, Higgs/particle theory, string theory, etc
- deleted 8y ago[deleted]
- rohan1024 8y agoNot a physics expert. Projecting in the air without a screen could be a potential use.
- sudhirj 8y agoThat still seems impractical, at least until we miniaturize a particle accelerator. The event is so improbable (two photons banging into each other) that you need a super dense cloud of them to get a measurable effect.
- db48x 8y agoLol, no. Photon-photon scattering is very rare; you only expect it to happen in very high-energy situations. To scatter enough photons to create a visible image in the air you would need to pour so much energy into the air that it would turn into a plasma. A deadly radioactive plasma that explodes outward from your holographic display and kills everyone nearby. This would not be considered practical.
- YaxelPerez 8y agoI know a couple rouge nation-states that might be interested
- SomeHacker44 8y agoRouge? Communist? “Better dead than rouge?” Hm.
- edf13 8y agoThe lol isn’t needed
- lugg 8y agoNeither is the rouge but here we are.
- deleted 8y ago[deleted]
- Iwan-Zotow 8y agoSure making real Jedi saber
- igravious 8y agoThank you Would have been nice if that info was featured somewhere in the article. I don't like to say it but this am I correct in saying that this article gives off the impression that this is an experimental first in terms of directly observing this photonic interaction?
- Blackbeard_ 8y agoThey do try to mitigate this criticism in the first line of the article: "Light-by-light scattering is a very rare phenomenon in which two photons – particles of light – interact, producing again a pair of photons." This is the process that they observe (for the first time) whereas E144 observed the Breit-Wheeler process. You can argue that this is too narrow a definition of light-by-light scattering but they have at least tried to make it self consistent...