LHC: definitivamente sicuro

[lowenz]

http://www.universetoday.com/2008/06...rth-after-all/

Its official: We're not going to be blown up, smothered in stranglets, sucked into a black hole or turned into ooze by the Large Hadron Collider (LHC). To put any concerns to rest, CERN (the European Organization for Nuclear Research) has concluded in another approved safety report that the LHC is harmless and will not hurt us, our planet or the Universe. This new investigation builds on previous findings that the LHC is safe, reiterating what scientists have been telling us for years. Besides, the LHC isn't doing anything that nature isn't already doing every second…

I actually thought the LHC safety reports were done and dusted (the original report was actually completed in 2003), but it seems, to be thorough, CERN wanted to re-confirm their previous conclusions that the LHC was safe and ready for use later this year.

The LHC is understandably under intense scrutiny and will be subject to a range of audits from safety to environmental impact. This new report commissioned to investigate whether any of the theoretical particles created in the LHC collision chamber could pose a threat, not only to the cows and sheep in the Swiss countryside, but to the Earth and the Cosmos. Strengthened with experimental and observational research, the new report prepared by a team of physicists at CERN, UC Santa Barbara and the Institute for Nuclear Research of the Russian Academy of Sciences, has covered all the factors from previous safety investigations, and again concluded that the LHC is… safe.

As with any high-energy experiment, scientists and governments are under increased pressure to ensure every step is being taken to safeguard against any catastrophic accident. The LHC, soon to be the world's most powerful particle accelerator, has seen more criticism than most physics experiments. For one, it is expensive (£2.4 billion or $4.7 billion), so collaborating governments and institutions want to know where their money is going, but second, CERN wants to avoid public misconceptions about what harm the LHC could do. This is epitomised in a recent lawsuit a Hawaiian man filed against CERN, citing the new accelerator might generate a black hole (that the Earth would get sucked into) or create a chain reaction, unleashing exotic "stranglets" on the planet. This is an extreme case of a misconception about what the LHC is capable of, so it seems essential that in-depth studies into LHC safety must be carried out continuously.

Listed is the safety reports perceived LHC threats (with likelihood of occurrence in parentheses):

* Microscopic black holes (not very likely): Although it would be pretty cool if micro-black holes were generated, the report concludes that this event will be unlikely, although theoretically possible. If a micro-black hole was produced by an LHC collision, it is very likely that it would evaporate very quickly (via Hawking Radiation), making it difficult for any observation attempt. If a micro-black hole was produced but it didn't evaporate (which isn't possible, in theory), depending on its charge, it would behave differently. Charged, the micro-black hole could interact with matter and get stopped as it tries to pass through the Earth. Un-charged, the micro-black hole will pass straight through the Earth and into space (as it will be weakly interacting) or simply hang around inside our planet. We know collisions between cosmic rays and the Earth's atmosphere happen naturally, often at higher energies than the LHC. Therefore, if micro-black holes are possible, the only option would be that they evaporate very quickly.. Besides, even if they were stable, they cannot suck in any matter and grow because they will have minimal gravitational influence over matter. Boring really…
* Strangelets (practically impossible): This hypothetical "strange matter" (containing up, down and strange quarks) could theoretically change ordinary matter into strange matter in a thousand-millionth of a second. This possibility was raised in 2000 before the opening of the Relativistic Heavy Ion Collider (RHIC) in the US. This collider uses heavier particles than most of the LHC tests and therefore more likely to produce stranglets. In fact some of its experiments are set up to detect this strange matter. No stranglets have been found in eight years; not only that, but the chain reaction theorized (turning the world into a clump of strangeness) has no experimental foundation. Stranglets do not exist, and the LHC will not produce them.
* Vacuum bubbles (practically impossible): Perhaps the Universe is not in its most stable configuration. Perturbations generated by the LHC could push it into a more stable state (a vacuum bubble), destroying the Universe as we know it. Not very likely. Again, collisions of higher energies happen throughout the cosmos, let alone in our own atmosphere, we're still here, our Universe is still here (or is it?).
* Magnetic monopoles (practically impossible): Hypothetical particles with a single magnetic pole, either north or south. If they could exist, they might mess around with protons possibly causing them to spontaneously decay. There is no reason to suspect they can exist, and even if they did, they could not be produced by the LHC as they are too heavy. Again, cosmic rays come to the rescue; as the high energy natural particle hit the atmosphere, their collisional energy is higher than the LHC. No magnetic monopoles, not end of the world.

Is that all there is? Surely there are more new and inventive ways to destroy the planet? Oh well…

[lowenz]

Per chi volesse un sunto visivo (e simpatico) su LHC e ATLAS:

http://www.youtube.com/TheATLASExperiment

http://www.youtube.com/watch?v=OxENLH1ATV4
http://www.youtube.com/watch?v=iYRQpcJVQx8
http://www.youtube.com/watch?v=DUkzyDbMQ3E

[FlatEric]

O santa patata credevano che si possano fare dei monopoli magnetici? Magari!!!!

[stbarlet]

Originariamente inviato da lowenz

Per chi volesse un sunto visivo (e simpatico) su LHC e ATLAS:

http://www.youtube.com/TheATLASExperiment

http://www.youtube.com/watch?v=OxENLH1ATV4
http://www.youtube.com/watch?v=iYRQpcJVQx8
http://www.youtube.com/watch?v=DUkzyDbMQ3E

Perchè parla di "calorimetri" ? E' un modo per intendere la funzione tipica dei calorimetri?

[lowenz]

Originariamente inviato da stbarlet

Perchè parla di "calorimetri" ? E' un modo per intendere la funzione tipica dei calorimetri?

E' una bella domanda

[lowenz]

Qui c'è l'articolo originale:

http://public.web.cern.ch/public/en/LHC/Safety-en.html

[fabrylama]

Originariamente inviato da stbarlet

Perchè parla di "calorimetri" ? E' un modo per intendere la funzione tipica dei calorimetri?

un calorimetro è un qualsiasi strumento che misura il flusso di calore, in questo caso si misura il calore sviluppato dall'assorbimento della particella da parte del rivelatore (e dal conseguente sciame di particelle), in tal modo si misura l'energia delle particelle assorbite, mettendo più calorimetri sottilissimi uno dietro l'altro si risale anche alla traiettoria della particella.

[stbarlet]

Originariamente inviato da fabrylama

un calorimetro è un qualsiasi strumento che misura il flusso di calore, in questo caso si misura il calore sviluppato dall'assorbimento della particella da parte del rivelatore (e dal conseguente sciame di particelle), in tal modo si misura l'energia delle particelle assorbite, mettendo più calorimetri sottilissimi uno dietro l'altro si risale anche alla traiettoria della particella.

Per quel che ne so, non viene rilevato un flusso di calore, ma un flusso di cariche/fotoni.. da qui la domanda.

[razziadacqua]

Cerchiamo di evitare di creare 10 3D sulla stessa cosa, avevo tanto bene inserito la stessa notizia in questa discussione...con tanto di link alle live webcams...
http://www.hwupgrade.it/forum/showth...1768388&page=2

[lowenz]

Originariamente inviato da razziadacqua

Cerchiamo di evitare di creare 10 3D sulla stessa cosa, avevo tanto bene inserito la stessa notizia in questa discussione...con tanto di link alle live webcams...
http://www.hwupgrade.it/forum/showth...1768388&page=2

Questo thread è una risposta in chiaro ai dubbi dei vari catastrofisti che girano per la rete, in modo tale che google lo indicizzi e possa rassicurare le persone con un po' di cervello

[laico79]

A prima vista mi sembrava che si parlasse di pornografia... lol

[GUSTAV]<]

Originariamente inviato da lowenz

Questo thread è una risposta in chiaro ai dubbi dei vari catastrofisti che girano per la rete, in modo tale che google lo indicizzi e possa rassicurare le persone con un po' di cervello

se siamo salvi è grazie a questo..
http://it.wikipedia.org/wiki/Radiazione_di_Hawking

[lowenz]

Originariamente inviato da laico79

A prima vista mi sembrava che si parlasse di pornografia... lol

Sicurezza, buchi neri

[killercode]

Originariamente inviato da lowenz

Questo thread è una risposta in chiaro ai dubbi dei vari catastrofisti che girano per la rete, in modo tale che google lo indicizzi e possa rassicurare le persone con un po' di cervello

Senza riferimenti a nessuno in particolare vero?

[gigio2005]

uffff....

niente distruzione della tessitura spazio-temporale dell'intero universo? che palle....

[lowenz]

Originariamente inviato da gigio2005

uffff....

niente distruzione della tessitura spazio-temporale dell'intero universo? che palle....

No, niente fuochi d'artificio spazio-temporali

[xenom]

Nuuuuu io volevo venire risucchiato da un buco neroooo

[GUSTAV]<]

Originariamente inviato da xenom

Nuuuuu io volevo venire risucchiato da un buco neroooo

consolati dai, pensa che potremmo anche essere colpiti da un asteroide..

[stbarlet]

Si può visitare il cern ? fino a che livelli?

[killercode]

Originariamente inviato da stbarlet

Si può visitare il cern ? fino a che livelli?

http://outreach.web.cern.ch/outreach.../Intro-en.html
Interessato anch'io, però deve essere un gruppo di almeno 12 persone, mi avevano invitato all'open Day ma ho dovuto rinunciare per impegni, e dal allora non sono più riuscito a formare un gruppo