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Safety of the LHC

Vigen — Fri, 22 May 2026 17:33:28 GMT

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	{{blockquote		{{blockquote
	\|text=''The operation of the LHC is safe, not only in the old sense of that word, but in the more general sense that our most qualified scientists have thoroughly considered and analyzed the risks involved in the operation of the LHC. [Any concerns] are merely hypothetical and speculative, and contradicted by much evidence and scientific analysis.''		\|text=''The operation of the LHC is safe, not only in the old sense of that word, but in the more general sense that our most qualified scientists have thoroughly considered and analyzed the risks involved in the operation of the LHC. [Any concerns] are merely hypothetical and speculative, and contradicted by much evidence and scientific analysis.''
	\|author=[[wikipedia:Sheldon Glashow\|Sheldon Glashow]] (Nobel Laureate in Physics, Boston U.), [[wikipedia:Frank Wilczek\|Frank Wilczek]] (Nobel Laureate in Physics, MIT), and [[wikipedia:Richard Wilson\|Richard Wilson]] (Mallinckrodt Professor of Physics, Harvard U.)		\|author=[[wikipedia:Sheldon Glashow\|Sheldon Glashow]] (Nobel Laureate in Physics, Boston U.), [[wikipedia:Frank Wilczek\|Frank Wilczek]] (Nobel Laureate in Physics, MIT), and [[wikipedia:Richard Wilson (physicist)\|Richard Wilson]] (Mallinckrodt Professor of Physics, Harvard U.)
	}}		}}

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	The paper by Giddings and Mangano<ref name=":0" /> has been peer-reviewed by anonymous experts in astrophysics and particle physics and published in the professional scientific journal ''[[wikipedia:Physical Review#Journals\|Physical Review D]]''. The American Physical Society chose to highlight this as one of the most significant papers it has published recently, commissioning a commentary<ref>{{Cite journal \|last=Peskin \|first=Michael \|date=2008-08-18 \|title=The end of the world at the Large Hadron Collider? \|url=https://link.aps.org/doi/10.1103/Physics.1.14 \|journal=Physics \|language=en \|volume=1 \|doi=10.1103/Physics.1.14 \|issn=1943-2879}}</ref> by Prof. Peskin from the Stanford Linear Accelerator Laboratory in which he endorses its conclusions. The Executive Committee of the Division of Particles and Fields of the American Physical Society has issued a statement endorsing the LSAG report.<ref>{{Cite web \|title=Statement by the Executive Committee of the DPF on the Safety of Collisions at the Large Hadron Collider \|url=http://www.aps.org/units/dpf/governance/reports/upload/lhc_saftey_statement.pdf \|archive-url=http://web.archive.org/web/20081001161427/http://www.aps.org/units/dpf/governance/reports/upload/lhc_saftey_statement.pdf \|archive-date=2008-10-01 \|access-date=2026-05-22 \|website=www.aps.org}}</ref>		The paper by Giddings and Mangano<ref name=":0" /> has been peer-reviewed by anonymous experts in astrophysics and particle physics and published in the professional scientific journal ''[[wikipedia:Physical Review#Journals\|Physical Review D]]''. The American Physical Society chose to highlight this as one of the most significant papers it has published recently, commissioning a commentary<ref>{{Cite journal \|last=Peskin \|first=Michael \|date=2008-08-18 \|title=The end of the world at the Large Hadron Collider? \|url=https://link.aps.org/doi/10.1103/Physics.1.14 \|journal=Physics \|language=en \|volume=1 \|doi=10.1103/Physics.1.14 \|issn=1943-2879}}</ref> by Prof. Peskin from the Stanford Linear Accelerator Laboratory in which he endorses its conclusions. The Executive Committee of the Division of Particles and Fields of the American Physical Society has issued a statement endorsing the LSAG report.<ref>{{Cite web \|title=Statement by the Executive Committee of the DPF on the Safety of Collisions at the Large Hadron Collider \|url=http://www.aps.org/units/dpf/governance/reports/upload/lhc_saftey_statement.pdf \|archive-url=http://web.archive.org/web/20081001161427/http://www.aps.org/units/dpf/governance/reports/upload/lhc_saftey_statement.pdf \|archive-date=2008-10-01 \|access-date=2026-05-22 \|website=www.aps.org}}</ref>

	The LSAG report has been published by the UK Institute of Physics in its publication Journal of Physics G.<ref name=":1" /> The conclusions of the LSAG report were endorsed in a press release that announced this publication.<ref>{{Cite web \|last=Physics \|first=Institute of \|title=LHC switch-on fears are completely unfounded \|url=https://www.iop.org/news/archive/page_64087.html \|archive-url=http://web.archive.org/web/20160403154528/https://www.iop.org/news/archive/page_64087.html \|archive-date=2016-04-03 \|access-date=2026-05-22 \|website=www.iop.org \|language=en-GB}}</ref>		The LSAG report has been published by the UK Institute of Physics in its publication ''Journal of Physics G''.<ref name=":1" /> The conclusions of the LSAG report were endorsed in a press release that announced this publication.<ref>{{Cite web \|last=Physics \|first=Institute of \|title=LHC switch-on fears are completely unfounded \|url=https://www.iop.org/news/archive/page_64087.html \|archive-url=http://web.archive.org/web/20160403154528/https://www.iop.org/news/archive/page_64087.html \|archive-date=2016-04-03 \|access-date=2026-05-22 \|website=www.iop.org \|language=en-GB}}</ref>

	The conclusions of LSAG have also been endorsed by the Particle and Nuclear Physics Section (KET) of the German Physical Society.<ref>{{Cite web \|title=Experten bestätigen: Der LHC ist sicher KET veröffentlicht Stellungnahme zu Schwarzen Löchern am LHC \|url=http://www.ketweb.de/oeffentlichkeitsarbeit/e204014/20080801_PM_Der_LHC_ist_sicher.pdf \|archive-url=http://web.archive.org/web/20140422201438/http://www.ketweb.de/oeffentlichkeitsarbeit/e204014/20080801_PM_Der_LHC_ist_sicher.pdf \|archive-date=2014-04-22 \|access-date=2026-05-22 \|website=www.ketweb.de \|language=DE}}</ref> A translation into German of the complete LSAG report may be found on the KET website.<ref>{{Cite web \|title=Bewertung der Sicherheit von Teilchenkollisionen am LHC \|url=https://lsag.web.cern.ch/LSAG-Report-German.pdf \|archive-url=https://web.archive.org/web/20241212105929/https://lsag.web.cern.ch/LSAG-Report-German.pdf \|archive-date=2024-12-12 \|access-date=2026-05-22 \|website=lsag.web.cern.ch \|language=DE}}</ref> (A translation into French of the complete LSAG report is also available.<ref>{{Cite web \|title=Rapport sur la sûreté des collisions au LHC \|url=https://lsag.web.cern.ch/LSAG-Report-French.pdf \|archive-url=https://web.archive.org/web/20241213000602/https://lsag.web.cern.ch/LSAG-Report-French.pdf \|archive-date=2024-12-13 \|access-date=2026-05-22 \|website=lsag.web.cern.ch \|language=FR}}</ref>)		The conclusions of LSAG have also been endorsed by the Particle and Nuclear Physics Section (KET) of the German Physical Society.<ref>{{Cite web \|title=Experten bestätigen: Der LHC ist sicher KET veröffentlicht Stellungnahme zu Schwarzen Löchern am LHC \|url=http://www.ketweb.de/oeffentlichkeitsarbeit/e204014/20080801_PM_Der_LHC_ist_sicher.pdf \|archive-url=http://web.archive.org/web/20140422201438/http://www.ketweb.de/oeffentlichkeitsarbeit/e204014/20080801_PM_Der_LHC_ist_sicher.pdf \|archive-date=2014-04-22 \|access-date=2026-05-22 \|website=www.ketweb.de \|language=DE}}</ref> A translation into German of the complete LSAG report may be found on the KET website.<ref>{{Cite web \|title=Bewertung der Sicherheit von Teilchenkollisionen am LHC \|url=https://lsag.web.cern.ch/LSAG-Report-German.pdf \|archive-url=https://web.archive.org/web/20241212105929/https://lsag.web.cern.ch/LSAG-Report-German.pdf \|archive-date=2024-12-12 \|access-date=2026-05-22 \|website=lsag.web.cern.ch \|language=DE}}</ref> (A translation into French of the complete LSAG report is also available.<ref>{{Cite web \|title=Rapport sur la sûreté des collisions au LHC \|url=https://lsag.web.cern.ch/LSAG-Report-French.pdf \|archive-url=https://web.archive.org/web/20241213000602/https://lsag.web.cern.ch/LSAG-Report-French.pdf \|archive-date=2024-12-13 \|access-date=2026-05-22 \|website=lsag.web.cern.ch \|language=FR}}</ref>)

Large Hadron Collider

Vigen — Fri, 22 May 2026 17:27:35 GMT

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	The '''Large Hadron Collider''' ('''LHC''') is the world's largest and highest-energy [[particle accelerator]].<ref name="TheLHC">{{cite web \|url=https://home.cern/topics/large-hadron-collider \|title=The Large Hadron Collider \|date=28 June 2023 \|publisher=CERN}}</ref><ref name="Harman">{{cite journal\|author=Joel Achenbach\|date=March 2012\|title=The God Particle\|url=http://ngm.nationalgeographic.com/2008/03/god-particle/achenbach-text\|archive-url=https://web.archive.org/web/20080225104327/http://ngm.nationalgeographic.com/2008/03/god-particle/achenbach-text\|archive-date=25 February 2008\|journal=[[National Geographic Magazine]]\|access-date=25 February 2008}}</ref> It was built by the [[CERN\|European Organization for Nuclear Research]] (CERN) between 1998 and 2008, in collaboration with over 10,000 scientists, and hundreds of universities and laboratories across more than 100 countries.<ref>{{cite news \|first=Roger \|last=Highfield \|date=16 September 2008 \|title=Large Hadron Collider: Thirteen ways to change the world \|url=https://www.telegraph.co.uk/science/large-hadron-collider/3351899/Large-Hadron-Collider-thirteen-ways-to-change-the-world.html \|archive-url=https://web.archive.org/web/20090924011335/http://www.telegraph.co.uk/science/large-hadron-collider/3351899/Large-Hadron-Collider-thirteen-ways-to-change-the-world.html \|archive-date=24 September 2009 \|work=[[The Daily Telegraph]] \|access-date=10 October 2008 \|location=London}}</ref> It lies in a tunnel 27 kilometres in circumference and as deep as 175 metres beneath the [[France–Switzerland border]] near [[Geneva]].		The '''Large Hadron Collider''' ('''LHC''') is the world's largest and highest-energy particle accelerator.<ref name="TheLHC">{{cite web \|url=https://home.cern/topics/large-hadron-collider \|title=The Large Hadron Collider \|date=28 June 2023 \|publisher=CERN}}</ref><ref name="Harman">{{cite journal\|author=Joel Achenbach\|date=March 2012\|title=The God Particle\|url=http://ngm.nationalgeographic.com/2008/03/god-particle/achenbach-text\|archive-url=https://web.archive.org/web/20080225104327/http://ngm.nationalgeographic.com/2008/03/god-particle/achenbach-text\|archive-date=25 February 2008\|journal=[[National Geographic Magazine]]\|access-date=25 February 2008}}</ref> It was built by the [[CERN\|European Organization for Nuclear Research]] (CERN) between 1998 and 2008, in collaboration with over 10,000 scientists, and hundreds of universities and laboratories across more than 100 countries.<ref>{{cite news \|first=Roger \|last=Highfield \|date=16 September 2008 \|title=Large Hadron Collider: Thirteen ways to change the world \|url=https://www.telegraph.co.uk/science/large-hadron-collider/3351899/Large-Hadron-Collider-thirteen-ways-to-change-the-world.html \|archive-url=https://web.archive.org/web/20090924011335/http://www.telegraph.co.uk/science/large-hadron-collider/3351899/Large-Hadron-Collider-thirteen-ways-to-change-the-world.html \|archive-date=24 September 2009 \|work=[[The Daily Telegraph]] \|access-date=10 October 2008 \|location=London}}</ref> It lies in a tunnel 27 kilometres in circumference and as deep as 175 metres beneath the France–Switzerland border near Geneva.

	The first collisions were achieved in 2010 at an energy of 3.5 [[tera-~~]][[electronvolt]]s~~ (TeV) per beam, about four times the previous world record.<ref name=bbc20100330>{{cite news \|work=BBC News \|date=30 March 2010 \|title=CERN LHC sees high-energy success \|url=https://news.bbc.co.uk/1/hi/sci/tech/8593780.stm\|access-date=30 March 2010}}</ref> The discovery of the [[Higgs boson]] at the LHC was announced in 2012. Between 2013 and 2015, the LHC was shut down and upgraded; after those upgrades it reached 6.5 TeV per beam (13.0 TeV total collision energy).<ref>{{cite web \|last1=O'Luanaigh\|first1=Cian\|title=Proton beams are back in the LHC\|url=http://home.web.cern.ch/about/updates/2015/04/proton-beams-are-back-lhc \|publisher=CERN \|access-date=24 April 2015}}</ref><ref name="2015restart">{{cite news \|url=https://www.bbc.co.uk/news/science-environment-32976838\|title=Large Hadron Collider turns on 'data tap'\|access-date=28 August 2015\|date=3 June 2015\|last1=Rincon\|first1=Paul}}</ref><ref>{{cite news \|url=https://www.bbc.co.uk/news/science-environment-32809636 \|title=LHC smashes energy record with test collisions\|access-date=28 August 2015\|date=21 May 2015\|last1=Webb\|first1=Jonathan}}</ref> At the end of 2018, it was shut down for maintenance and further upgrades, and reopened over three years later in April 2022.<ref>{{Cite web \|date=2023-10-07 \|title=2022 Digital Media Kit: Higgs10, LHC Run 3 and restart \|url=https://home.cern/press/2022 \|access-date=2023-10-10 \|website=CERN \|language=en}}</ref>		The first collisions were achieved in 2010 at an energy of 3.5 tera-electronvolts (TeV) per beam, about four times the previous world record.<ref name=bbc20100330>{{cite news \|work=BBC News \|date=30 March 2010 \|title=CERN LHC sees high-energy success \|url=https://news.bbc.co.uk/1/hi/sci/tech/8593780.stm\|access-date=30 March 2010}}</ref> The discovery of the Higgs boson at the LHC was announced in 2012. Between 2013 and 2015, the LHC was shut down and upgraded; after those upgrades it reached 6.5 TeV per beam (13.0 TeV total collision energy).<ref>{{cite web \|last1=O'Luanaigh\|first1=Cian\|title=Proton beams are back in the LHC\|url=http://home.web.cern.ch/about/updates/2015/04/proton-beams-are-back-lhc \|publisher=CERN \|access-date=24 April 2015}}</ref><ref name="2015restart">{{cite news \|url=https://www.bbc.co.uk/news/science-environment-32976838\|title=Large Hadron Collider turns on 'data tap'\|access-date=28 August 2015\|date=3 June 2015\|last1=Rincon\|first1=Paul}}</ref><ref>{{cite news \|url=https://www.bbc.co.uk/news/science-environment-32809636 \|title=LHC smashes energy record with test collisions\|access-date=28 August 2015\|date=21 May 2015\|last1=Webb\|first1=Jonathan}}</ref> At the end of 2018, it was shut down for maintenance and further upgrades, and reopened over three years later in April 2022.<ref>{{Cite web \|date=2023-10-07 \|title=2022 Digital Media Kit: Higgs10, LHC Run 3 and restart \|url=https://home.cern/press/2022 \|access-date=2023-10-10 \|website=CERN \|language=en}}</ref>

	The collider has four crossing points where the accelerated particles collide. [[#Detectors\|Nine detectors]],<ref name="FactsFiguresAnoutLHC">{{cite web \|title=Facts and figures about the LHC \|url=https://home.cern/resources/faqs/facts-and-figures-about-lhc \|publisher=CERN \|access-date=17 April 2023}}</ref> each designed to detect different phenomena, are positioned around the crossing points. The LHC primarily collides proton beams, but it can also accelerate beams of heavy [[ions]], such as in ~~[[lead]]–lead~~ collisions and [[proton]]–lead collisions.<ref>{{Cite web \|date=2023-10-07 \|title=Time for lead collisions in the LHC \|url=https://home.cern/news/news/accelerators/time-lead-collisions-lhc \|access-date=2023-10-10 \|website=CERN \|language=en}}</ref>		The collider has four crossing points where the accelerated particles collide. [[#Detectors\|Nine detectors]],<ref name="FactsFiguresAnoutLHC">{{cite web \|title=Facts and figures about the LHC \|url=https://home.cern/resources/faqs/facts-and-figures-about-lhc \|publisher=CERN \|access-date=17 April 2023}}</ref> each designed to detect different phenomena, are positioned around the crossing points. The LHC primarily collides proton beams, but it can also accelerate beams of heavy ions, such as in lead–lead collisions and [[proton]]–lead collisions.<ref>{{Cite web \|date=2023-10-07 \|title=Time for lead collisions in the LHC \|url=https://home.cern/news/news/accelerators/time-lead-collisions-lhc \|access-date=2023-10-10 \|website=CERN \|language=en}}</ref>

	The LHC's goal is to allow physicists to test the predictions of different theories of [[particle physics]], including measuring the properties of the Higgs boson,<ref>{{cite web \|year=2008 \|title=Missing Higgs \|url=http://public.web.cern.ch/public/en/Science/Higgs-en.html \|publisher=CERN \|access-date=10 October 2008 \|archive-date=18 February 2013 \|archive-url=https://web.archive.org/web/20130218020035/http://public.web.cern.ch/public/en/science/higgs-en.html }}</ref> searching for the large family of new particles predicted by ~~[[supersymmetry\|~~supersymmetric theories]],<ref>{{cite web \|year=2008 \|title=Towards a superforce \|url=http://public.web.cern.ch/public/en/Science/Superforce-en.html \|publisher=CERN \|access-date=10 October 2008 \|archive-date=18 February 2013 \|archive-url=https://web.archive.org/web/20130218015509/http://public.web.cern.ch/public/en/science/Superforce-en.html }}</ref> and studying other ~~[[List of unsolved problems in physics#High-energy physics/particle physics\|~~unresolved questions in particle physics]].		The LHC's goal is to allow physicists to test the predictions of different theories of particle physics, including measuring the properties of the Higgs boson,<ref>{{cite web \|year=2008 \|title=Missing Higgs \|url=http://public.web.cern.ch/public/en/Science/Higgs-en.html \|publisher=CERN \|access-date=10 October 2008 \|archive-date=18 February 2013 \|archive-url=https://web.archive.org/web/20130218020035/http://public.web.cern.ch/public/en/science/higgs-en.html }}</ref> searching for the large family of new particles predicted by supersymmetric theories,<ref>{{cite web \|year=2008 \|title=Towards a superforce \|url=http://public.web.cern.ch/public/en/Science/Superforce-en.html \|publisher=CERN \|access-date=10 October 2008 \|archive-date=18 February 2013 \|archive-url=https://web.archive.org/web/20130218015509/http://public.web.cern.ch/public/en/science/Superforce-en.html }}</ref> and studying other unresolved questions in particle physics.

			For more information see [[wikipedia:Large_Hadron_Collider\|Wikipedia]].
	For more information see [[wikipedia:Large_Hadron_Collider\|Wikipedia]]
	[[Category:CERN particle accelerators]]		[[Category:CERN particle accelerators]]
	<references />		<references />
	[[Category:LHC]]		[[Category:LHC]]

Safety of the LHC

Vigen — Fri, 22 May 2026 17:25:50 GMT

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	A hypothetical scenario for possibly dangerous metastable black holes has recently been proposed by Dr. Plaga.<ref>{{Citation \|last=Plaga \|first=R. \|title=On the potential catastrophic risk from metastable quantum-black holes produced at particle colliders \|date=2009-08-09 \|url=http://arxiv.org/abs/0808.1415 \|access-date=2026-05-22 \|publisher=arXiv \|doi=10.48550/arXiv.0808.1415 \|id=arXiv:0808.1415}}</ref> The conclusions of this work have been shown to be inconsistent in a second paper by Giddings and Mangano,<ref>{{Citation \|last=Giddings \|first=Steven B. \|title=Comments on claimed risk from metastable black holes \|date=2008-08-29 \|url=http://arxiv.org/abs/0808.4087 \|access-date=2026-05-22 \|publisher=arXiv \|doi=10.48550/arXiv.0808.4087 \|id=arXiv:0808.4087 \|last2=Mangano \|first2=Michelangelo L.}}</ref> where it is also stated that the safety of this class of metastable black hole scenarios is already established by their original work.<ref name=":0" />		A hypothetical scenario for possibly dangerous metastable black holes has recently been proposed by Dr. Plaga.<ref>{{Citation \|last=Plaga \|first=R. \|title=On the potential catastrophic risk from metastable quantum-black holes produced at particle colliders \|date=2009-08-09 \|url=http://arxiv.org/abs/0808.1415 \|access-date=2026-05-22 \|publisher=arXiv \|doi=10.48550/arXiv.0808.1415 \|id=arXiv:0808.1415}}</ref> The conclusions of this work have been shown to be inconsistent in a second paper by Giddings and Mangano,<ref>{{Citation \|last=Giddings \|first=Steven B. \|title=Comments on claimed risk from metastable black holes \|date=2008-08-29 \|url=http://arxiv.org/abs/0808.4087 \|access-date=2026-05-22 \|publisher=arXiv \|doi=10.48550/arXiv.0808.4087 \|id=arXiv:0808.4087 \|last2=Mangano \|first2=Michelangelo L.}}</ref> where it is also stated that the safety of this class of metastable black hole scenarios is already established by their original work.<ref name=":0" />

	== ~~Additional sources~~ ==		== Further reading ==

	* Summary of the LSAG report. Translations are available in the following languages : fr de el es it jp no pl ru.		* Summary of the LSAG report. Translations are available in the following languages : fr de el es it jp no pl ru.
	* Specialist report published in Europe (2003): [http://dx.doi.org/10.5170/CERN-2003-001 Study of potentially dangerous events during heavy-ion collisions at the LHC : report of the LHC safety study group].		* Specialist report published in Europe (2003): [http://dx.doi.org/10.5170/CERN-2003-001 Study of potentially dangerous events during heavy-ion collisions at the LHC : report of the LHC safety study group].
	* [https://arxiv.org/abs/hep-ph/9910333 Specialist report published in the United States (1999): Review of speculative "disaster scenarios" at RHIC].		* [https://arxiv.org/abs/hep-ph/9910333 Specialist report published in the United States (1999): Review of speculative "disaster scenarios" at RHIC].
			* Wikipedia: [[Wikipedia:Safety of high-energy particle collision experiments\|Safety of high-energy particle collision experiments]]

	== References ==		== References ==
	<references />		<references />
			[[Category:LHC]]

Category:CS1 français-language sources (fr)

Vigen — Fri, 22 May 2026 17:23:41 GMT

Created page with "__HIDDENCAT__"

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Category:CS1 Deutsch-language sources (de)

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Safety of the LHC

Vigen — Fri, 22 May 2026 15:34:49 GMT

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 The LSAG report has been published by the UK Institute of Physics in its publication Journal of Physics G.<ref name=":1" /> The conclusions of the LSAG report were endorsed in a press release that announced this publication.<ref>{{Cite web |last=Physics |first=Institute of |title=LHC switch-on fears are completely unfounded |url=https://www.iop.org/news/archive/page_64087.html |archive-url=http://web.archive.org/web/20160403154528/https://www.iop.org/news/archive/page_64087.html |archive-date=2016-04-03 |access-date=2026-05-22 |website=www.iop.org |language=en-GB}}</ref>
 == References ==
 <references />

Safety of the LHC

Vigen — Fri, 22 May 2026 09:34:10 GMT

Created page with "The Large Hadron Collider (LHC) can achieve an energy that no other particle accelerators have reached before, but Nature routinely produces higher energies in cosmic-ray collisions. Concerns about the safety of whatever may be created in such high-energy particle collisions have been addressed for many years. In the light of new experimental data and theoretical understanding, the LHC Safety Assessment Group (LSAG) has updated a review of the analysis made in 20..."

New page

The [[Large Hadron Collider]] (LHC) can achieve an energy that no other particle accelerators have reached before, but Nature routinely produces higher energies in cosmic-ray collisions. Concerns about the safety of whatever may be created in such high-energy particle collisions have been addressed for many years. In the light of new experimental data and theoretical understanding, the LHC Safety Assessment Group ([[LSAG]]) has updated a review of the analysis made in 2003 by the LHC Safety Study Group, a group of independent scientists.

LSAG reaffirms and extends the conclusions of the 2003 report that LHC collisions present no danger and that there are no reasons for concern. Whatever the LHC will do, Nature has already done many times over during the lifetime of the Earth and other astronomical bodies. The LSAG report has been reviewed and endorsed by CERN’s Scientific Policy Committee, a group of external scientists that advises CERN’s governing body, its Council.

''The following summarises the main arguments given in the'' LSAG report''.<ref>{{Cite journal |last=Ellis |first=John R. |last2=Giudice |first2=Gian |last3=Mangano |first3=Michelangelo L. |last4=Tkachev |first4=Igor |last5=Wiedemann |first5=Urs |date=2008 |title=Review of the Safety of LHC Collisions |url=https://cds.cern.ch/record/1111112 |journal=J. Phys. G |volume=35 |issue=11 |pages=115004 |doi=10.1088/0954-3899/35/11/115004}}</ref> Anyone interested in more details is encouraged to consult it directly, and the technical scientific papers to which it refers.''

== Cosmic rays ==
The LHC, like other particle accelerators, recreates the natural phenomena of cosmic rays<ref>{{Cite web |title=Cosmic rays: particles from outer space |url=https://home.web.cern.ch/science/physics/cosmic-rays-particles-outer-space |archive-url=https://web.archive.org/web/20250930155540/https://home.web.cern.ch/science/physics/cosmic-rays-particles-outer-space |archive-date=2025-09-30 |access-date=2026-05-22 |website=CERN |language=en}}</ref> under controlled laboratory conditions, enabling them to be studied in more detail. Cosmic rays are particles produced in outer space, some of which are accelerated to energies far exceeding those of the LHC. The energy and the rate at which they reach the Earth’s atmosphere have been measured in experiments for some 70 years. Over the past billions of years, Nature has already generated on Earth as many collisions as about a million LHC experiments – and the planet still exists. Astronomers observe an enormous number of larger astronomical bodies throughout the Universe, all of which are also struck by cosmic rays. The Universe as a whole conducts more than 10 million million LHC-like experiments per second. The possibility of any dangerous consequences contradicts what astronomers see—stars and galaxies still exist.

== Microscopic black holes ==
Nature forms black holes when certain stars, much larger than our Sun, collapse on themselves at the end of their lives. They concentrate a very large amount of matter in a very small space. Speculations about microscopic black holes at the LHC refer to particles produced in the collisions of pairs of protons, each of which has an energy comparable to that of a mosquito in flight. Astronomical black holes are much heavier than anything that could be produced at the LHC.

According to the well-established properties of gravity, described by Einstein’s relativity, it is impossible for microscopic black holes to be produced at the LHC. There are, however, some speculative theories that predict the production of such particles at the LHC. All these theories predict that these particles would disintegrate immediately. Black holes, therefore, would have no time to start accreting matter and to cause macroscopic effects.

Although theory predicts that microscopic black holes decay rapidly, even hypothetical stable black holes can be shown to be harmless by studying the consequences of their production by cosmic rays. Whilst collisions at the LHC differ from cosmic-ray collisions with astronomical bodies like the Earth in that new particles produced in LHC collisions tend to move more slowly than those produced by cosmic rays, one can still demonstrate their safety. The specific reasons for this depend whether the black holes are electrically charged, or neutral. Many stable black holes would be expected to be electrically charged, since they are created by charged particles. In this case they would interact with ordinary matter and be stopped while traversing the Earth or Sun, whether produced by cosmic rays or the LHC. The fact that the Earth and Sun are still here rules out the possibility that cosmic rays or the LHC could produce dangerous charged microscopic black holes. If stable microscopic black holes had no electric charge, their interactions with the Earth would be very weak. Those produced by cosmic rays would pass harmlessly through the Earth into space, whereas those produced by the LHC could remain on Earth. However, there are much larger and denser astronomical bodies than the Earth in the Universe. Black holes produced in cosmic-ray collisions with bodies such as neutron stars and white dwarf stars would be brought to rest. The continued existence of such dense bodies, as well as the Earth, rules out the possibility of the LHC producing any dangerous black holes.

== Strangelets ==
Strangelet is the term given to a hypothetical microscopic lump of ‘strange matter’ containing almost equal numbers of particles called up, down and strange quarks. According to most theoretical work, strangelets should change to ordinary matter within a thousand-millionth of a second. But could strangelets coalesce with ordinary matter and change it to strange matter? This question was first raised before the start up of the Relativistic Heavy Ion Collider, RHIC, in 2000 in the United States. A study at the time showed that there was no cause for concern, and RHIC has now run for eight years, searching for strangelets without detecting any. At times, the LHC will run with beams of heavy nuclei, just as RHIC does. The LHC’s beams will have more energy than RHIC, but this makes it even less likely that strangelets could form. It is difficult for strange matter to stick together in the high temperatures produced by such colliders, rather as ice does not form in hot water. In addition, quarks will be more dilute at the LHC than at RHIC, making it more difficult to assemble strange matter. Strangelet production at the LHC is therefore less likely than at RHIC, and experience there has already validated the arguments that strangelets cannot be produced.

The analysis of the first LHC data from heavy ion collisions has now confirmed the key ingredients used in the LSAG report to evaluate the upper limit on the production of hypothetical strangelets. For more details see this addendum to the LSAG report: ''Implications of LHC heavy ion data for multi-strange baryon production'' (2011).<ref>{{Citation |title=Implications of LHC heavy ion data for multi-strange baryon production |date=2011 |url=https://cds.cern.ch/record/2959318 |access-date=2026-05-22 |doi=10.17181/CERN.T914.LBN1}}</ref>

== Vacuum bubbles ==
There have been speculations that the Universe is not in its most stable configuration, and that perturbations caused by the LHC could tip it into a more stable state, called a vacuum bubble, in which we could not exist. If the LHC could do this, then so could cosmic-ray collisions. Since such vacuum bubbles have not been produced anywhere in the visible Universe, they will not be made by the LHC.

== Magnetic monopoles ==
Magnetic monopoles are hypothetical particles with a single magnetic charge, either a north pole or a south pole. Some speculative theories suggest that, if they do exist, magnetic monopoles could cause protons to decay. These theories also say that such monopoles would be too heavy to be produced at the LHC. Nevertheless, if the magnetic monopoles were light enough to appear at the LHC, cosmic rays striking the Earth’s atmosphere would already be making them, and the Earth would very effectively stop and trap them. The continued existence of the Earth and other astronomical bodies therefore rules out dangerous proton-eating magnetic monopoles light enough to be produced at the LHC.

== Other aspects of LHC safety ==
Concern has recently been expressed that a 'runaway fusion reaction' might be created in the LHC carbon beam dump. The safety of the LHC beam dump had previously been reviewed by the relevant regulatory authorities of the CERN host states, France and Switzerland. The specific concerns expressed more recently have been addressed in a technical memorandum by Assmann ''et al.''<ref>{{Citation |last=Assmann |first=R |title=Interaction of the CERN Large Hadron Collider (LHC) beam with the beam dump block |date=2008 |url=https://cds.cern.ch/record/2959319 |access-date=2026-05-22 |doi=10.17181/CERN.1WMJ.6HQR |last2=Ferrari |first2=A |last3=Goddard |first3=B |last4=Schmidt |first4=R |last5=Tahir |first5=N A}}</ref> As they point out, fusion reactions can be maintained only in material compressed by some external pressure, such as that provided by gravity inside a star, a fission explosion in a thermonuclear device, a magnetic field in a Tokamak, or by continuing isotropic laser or particle beams in the case of inertial fusion. In the case of the LHC beam dump, it is struck once by the beam coming from a single direction. There is no countervailing pressure, so the dump material is not compressed, and no fusion is possible.

{{blockquote
|text=''To think that LHC particle collisions at high energies can lead to dangerous black holes is rubbish. Such rumors were spread by unqualified people seeking sensation or publicity.''
|author=[[wikipedia:Vitaly Ginzburg|Vitaly Ginzburg]]
|source=Nobel Laureate in Physics, Lebedev Physical Institute, Moscow, and the Russian Academy of Sciences
}}Concern has been expressed that a 'runaway fusion reaction' might be created in a nitrogen tank inside the LHC tunnel. There are no such nitrogen tanks. Moreover, the arguments in the previous paragraph prove that no fusion would be possible even if there were.

Finally, concern has also been expressed that the LHC beam might somehow trigger a "Bose-Nova" in the liquid helium used to cool the LHC magnets. A study by Fairbairn and McElrath has clearly shown there is no possibility of the LHC beam triggering a fusion reaction in helium.<ref>{{Citation |last=Fairbairn |first=Malcolm |title=There is no explosion risk associated with superfluid Helium in the LHC cooling system |date=2008-09-23 |url=http://arxiv.org/abs/0809.4004 |access-date=2026-05-22 |publisher=arXiv |doi=10.48550/arXiv.0809.4004 |id=arXiv:0809.4004 |last2=McElrath |first2=Bob}}</ref>

{{blockquote
|text=''The operation of the LHC is safe, not only in the old sense of that word, but in the more general sense that our most qualified scientists have thoroughly considered and analyzed the risks involved in the operation of the LHC. [Any concerns] are merely hypothetical and speculative, and contradicted by much evidence and scientific analysis.''
|author=[[wikipedia:Sheldon Glashow|Sheldon Glashow]] (Nobel Laureate in Physics, Boston U.), [[wikipedia:Frank Wilczek|Frank Wilczek]] (Nobel Laureate in Physics, MIT), and [[wikipedia:Richard Wilson|Richard Wilson]] (Mallinckrodt Professor of Physics, Harvard U.)
}}

==== Comments on the papers by Giddings and Mangano, and by LSAG ====
The papers by Giddings and Mangano<ref name=":0">{{Cite journal |last=Giddings |first=Steven B. |last2=Mangano |first2=Michelangelo M. |date=2008-08-18 |title=Astrophysical implications of hypothetical stable TeV-scale black holes |url=http://arxiv.org/abs/0806.3381 |journal=Physical Review D |volume=78 |issue=3 |pages=035009 |doi=10.1103/PhysRevD.78.035009 |issn=1550-7998}}</ref> and LSAG<ref name=":1">{{Cite journal |last=Ellis |first=John R. |last2=Giudice |first2=Gian |last3=Mangano |first3=Michelangelo L. |last4=Tkachev |first4=Igor |last5=Wiedemann |first5=Urs |date=2008 |title=Review of the Safety of LHC Collisions |url=https://cds.cern.ch/record/1111112 |journal=J. Phys. G |volume=35 |issue=11 |pages=115004 |doi=10.1088/0954-3899/35/11/115004}}</ref> demonstrating the safety of the LHC have been studied, reviewed and endorsed by leading experts from the CERN Member States, Japan, Russia and the United States, working in astrophysics, cosmology, general relativity, mathematics, particle physics and risk analysis, including several Nobel Laureates in Physics. They all agree that the LHC is safe.

The paper by Giddings and Mangano<ref name=":0" /> has been peer-reviewed by anonymous experts in astrophysics and particle physics and published in the professional scientific journal ''[[wikipedia:Physical Review#Journals|Physical Review D]]''. The American Physical Society chose to highlight this as one of the most significant papers it has published recently, commissioning a commentary<ref>{{Cite journal |last=Peskin |first=Michael |date=2008-08-18 |title=The end of the world at the Large Hadron Collider? |url=https://link.aps.org/doi/10.1103/Physics.1.14 |journal=Physics |language=en |volume=1 |doi=10.1103/Physics.1.14 |issn=1943-2879}}</ref> by Prof. Peskin from the Stanford Linear Accelerator Laboratory in which he endorses its conclusions. The Executive Committee of the Division of Particles and Fields of the American Physical Society has issued a statement endorsing the LSAG report.<ref>{{Cite web |title=Statement by the Executive Committee of the DPF on the Safety of Collisions at the Large Hadron Collider |url=http://www.aps.org/units/dpf/governance/reports/upload/lhc_saftey_statement.pdf |archive-url=http://web.archive.org/web/20081001161427/http://www.aps.org/units/dpf/governance/reports/upload/lhc_saftey_statement.pdf |archive-date=2008-10-01 |access-date=2026-05-22 |website=www.aps.org}}</ref>

The LSAG report has been published by the UK Institute of Physics in its publication Journal of Physics G.<ref name=":1" /> The conclusions of the LSAG report were endorsed in a press release that announced this publication.<ref>{{Cite web |last=Physics |first=Institute of |title=LHC switch-on fears are completely unfounded |url=https://www.iop.org/news/archive/page_64087.html |archive-url=http://web.archive.org/web/20160403154528/https://www.iop.org/news/archive/page_64087.html |archive-date=2016-04-03 |access-date=2026-05-22 |website=www.iop.org |language=en-GB}}</ref>

== References ==
<references />

LSAG

Vigen — Fri, 22 May 2026 07:41:26 GMT

Created page with "LHC Safety Assessment Group Category:Abbreviations Category:LHC"

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LHC Safety Assessment Group
[[Category:Abbreviations]]
[[Category:LHC]]

Cernipedia:About

Vigen — Thu, 21 May 2026 04:16:54 GMT

← Older revision		Revision as of 04:16, 21 May 2026
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	Within the context of CERN, the development of CERNipedia represents an effort to create a structured repository of knowledge related specifically to CERN’s history, people, ~~infrastructure~~, and the specific high-energy physics (HEP) jargon.		Within the context of CERN, the development of CERNipedia represents an effort to create a structured repository of knowledge related specifically to CERN’s history, people, infrastructures, and the specific high-energy physics (HEP) jargon.

Cernipedia:About

Vigen — Thu, 21 May 2026 04:16:26 GMT

Created page with "Within the context of CERN, the development of CERNipedia represents an effort to create a structured repository of knowledge related specifically to CERN’s history, people, infrastructure, and the specific high-energy physics (HEP) jargon."

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Within the context of CERN, the development of CERNipedia represents an effort to create a structured repository of knowledge related specifically to CERN’s history, people, infrastructure, and the specific high-energy physics (HEP) jargon.

Cernipedia:General disclaimer

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Cernipedia:General disclaimer

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Created page with "CERNipedia is based on the same principles as Wikimedia [https://foundation.wikimedia.org/wiki/Policy:Terms_of_Use]. '''Anybody is free to:''' * Read and print our articles and other media free of charge * Share and reuse our articles and other media under free and open licenses '''Anybody with a CERN computing account is free to:''' * Contribute content and edit material '''Under the following conditions:''' * Responsibility — Contributors take responsibility for t..."

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CERNipedia is based on the same principles as Wikimedia [https://foundation.wikimedia.org/wiki/Policy:Terms_of_Use].

'''Anybody is free to:'''
* Read and print our articles and other media free of charge
* Share and reuse our articles and other media under free and open licenses

'''Anybody with a CERN computing account is free to:'''
* Contribute content and edit material

'''Under the following conditions:'''
* Responsibility — Contributors take responsibility for their edits (since CERNipedia only host the content).
* Civility — Contributors support a civil environment and do not harass other users.
* Lawful behavior — Contributors do not violate copyright, post illegal content, or violate other applicable laws that follow human rights principles and CERN regulations.
* No Harm — Contributors do not harm our technology infrastructure and follow the policies for the infrastructure [https://cds.cern.ch/record/2842993/files/OC%205%20Rev1%20.pdf].
* Terms of use and policies — Contributors adhere to the below Terms of Use, to the CERN Code of Conduct [https://repository.cern/records/fe7kx-e4a22/preview/BrochureCodeofConductEN.pdf], and to the applicable community policies.

'''With the understanding that:'''
* Contributors license freely their contributions — Contributors generally must license their contributions and edits to CERNipedia under a free and open license (unless the contribution is in the public domain).
* No professional advice — The content of articles on CERNipedia is for informational purposes only and does not constitute professional advice.

---Terms of Use---
The Terms of Use for Wikipedia are the same as for Wikimedia [https://foundation.wikimedia.org/wiki/Policy:Terms_of_Use], unless CERN regulations are stricter.

Cernipedia:Privacy policy

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Created page with "Contributors to CERNipedia are subject to CERN rules, in particular as outlined in: * Operational Circular No. 05 (Rev. 1 - January 2023): Use of CERN computing facilities [https://cds.cern.ch/record/2842993/files/OC%205%20Rev1%20.pdf] * Operational Circular No. 11 (Rev.1) – The Processing of Personal Data at CERN [https://cds.cern.ch/record/2953827/files/CERN_Circ_Op_Angl_No11_rev1.pdf] All contributors are solely responsible for the information added to the platform."

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Contributors to CERNipedia are subject to CERN rules, in particular as outlined in:
* Operational Circular No. 05 (Rev. 1 - January 2023): Use of CERN computing facilities [https://cds.cern.ch/record/2842993/files/OC%205%20Rev1%20.pdf]
* Operational Circular No. 11 (Rev.1) – The Processing of Personal Data at CERN [https://cds.cern.ch/record/2953827/files/CERN_Circ_Op_Angl_No11_rev1.pdf]

All contributors are solely responsible for the information added to the platform.

The CERN Library

Vigen — Mon, 18 May 2026 12:34:05 GMT

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	The CERN Library has been in operation since the Organization was founded in 1954. The renovation work, completed in 2022, has expanded and modernized the library’s offerings, with the aim of providing a welcoming, functional space that meets the needs of employees <ref name=":1">CERN website, https://home.cern/new-cern-library-one-year/</ref>.		The CERN Library has been in operation since the Organization was founded in 1954. The renovation work, completed in 2022, has expanded and modernized the library’s offerings, with the aim of providing a welcoming, functional space that meets the needs of employees <ref name=":1">CERN website, https://home.cern/new-cern-library-one-year/</ref>.

	The library is part of the [[SIS\|Scientific Information Service]] (SIS), a department that also includes the CERN Archives, the Open Science service, and the [[INSPIRE]] platform, a leading resource for literature in particle physics <ref>The Scientific Information Service's website, https://sis.web.cern.ch/about-us/structure</ref>.		The library is part of the [[SIS\|Scientific Information Service]] (SIS), a department that also includes the [[CERN Archives]], the Open Science service, and the [[INSPIRE]] platform, a leading resource for literature in particle physics <ref>The Scientific Information Service's website, https://sis.web.cern.ch/about-us/structure</ref>.

	== The collection ==		== The collection ==

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	'''Anybody is free to:'''		'''Anybody is free to:'''
	* Read and print our articles and other media free of charge		* Read and print our articles and other media free of charge.
	* Share and reuse our articles and other media under free and open licenses		* Share and reuse our articles and other media under free and open licenses.

	'''Anybody with a CERN computing account is free to:'''		'''Anybody with a CERN computing account is free to:'''
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	'''Under the following conditions:'''		'''Under the following conditions:'''
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	* Civility — Contributors support a civil environment and do not harass other users.		* Civility — Contributors support a civil environment and do not harass other users.
	* Lawful behavior — Contributors do not violate copyright, post illegal content, or violate other applicable laws that follow human rights principles and CERN regulations.		* Lawful behavior — Contributors do not violate copyright, post illegal content, or violate other applicable laws that follow human rights principles and CERN regulations.
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	* Terms of use and policies — Contributors adhere to the below Terms of Use, to the CERN Code of Conduct [https://repository.cern/records/fe7kx-e4a22/preview/BrochureCodeofConductEN.pdf], and to the applicable community policies.		* Terms of use and policies — Contributors adhere to the below Terms of Use, to the CERN Code of Conduct [https://repository.cern/records/fe7kx-e4a22/preview/BrochureCodeofConductEN.pdf], and to the applicable community policies.

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	* No professional advice — The content of articles on CERNipedia is for informational purposes only and does not constitute professional advice.		* No professional advice — The content of articles on CERNipedia is for informational purposes only and does not constitute professional advice.

	~~---~~Terms of Use~~---~~		== Terms of Use ==
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