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Faster than the speed of light Was Einstein wrong?. The Big Bang, the LHC and the God Particle. Cormac O’Raifeartaigh (WIT). Cormac O’Raifeartaigh (WIT) Maths Week, CALMAST. Overview. I The experiment What, why, how II Skepticism from theory Special relativity
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Faster than the speed of light Was Einstein wrong? The Big Bang, the LHC and the God Particle Cormac O’Raifeartaigh (WIT) Cormac O’Raifeartaigh (WIT) Maths Week, CALMAST
Overview I The experiment What, why, how II Skepticism from theory Special relativity General relativity III Skepticism from experiment Particle experiments Astronomy Supernova observations IV Skepticism in science Coda: what if..?
Beam of neutrinos at CERN Detector under Gran Sasso Distance of 732 km Time of flight 2.43 ms The OPERA experiment Highly respected group Resultearly by 60 nanoseconds 0.003% faster than light!
Neutrinos • Suggested by Pauli (1930) • Conservation of energy • Zero charge, ‘zero’ mass • Weak interaction • Skepticism (non-physicists) Detected in 1956
Standard Model Higgs bosonoutstanding
Neutrinos today • Three different types • Tiny mass • Dark matter? • The solar neutrino paradox Neutrino oscillation • Gran Sasso experiment • Unexpected result Missing neutrinos
OPERA: the numbers • Time of flight: +/- 10ns 2.43006 +/- 0.00001 ms • Velocity = distance/time Δv/v = 2.5 x 10-5 or .003% • Measurement of distance (GPS) 732 km +/- 20 cm (18 m?) Note: neutrinos in pulses .01 ms long (10,000 ns)
Not direct comparison Light does not travel through mountain Accurate measurement of distance Relies on GPS Accurate measurement of time-of-flight Relies on GPS and statistics (pulses) Relatively short distance Need to direct beam at the moon Snags Expect: systematic error
II Skepticism from theory (SR) The special theory of relativity (1905) • Laws of physics identical for observers in uniform motion • Speed of light in vacuum a universal constant Distance not absolute Time not absolute Mass increases with velocity E = mc2 Reception: skepticism
Evidence for relativity • Early experiments Kaufmann, Bucherer • Modern particle accelerators Length contraction Time dilation Mass increase • Particle accelerators Speed limit Antimatter E = mc2
9 accelerators • velocity increase? K.E = 1/2mv2
Relativity ‘skepticism’ • Extraordinary concept • Counter-intuitive • Only observable at tremendous speeds • Only observable for subatomic particles Speed of light plays role of ∞ • Simple maths • Time and distance calculations • Personalization • Confusion of discovery and justification Dr Al Kelly ‘Einstein wrong’ The Irish Times Compare: quantum physics
Skepticism from theory (GR) General Relativity (1915) • Laws of physics identical for all observers • Speed of light in vacuum a universal constant • Principle of equivalence Gravity = curvature of space and time • New view of gravity • Revolution • Cosmological implications Matter warps space and time
General relativity • Predictions • Bending of starlight by sun • Black holes • Expanding universe • Time dilation by gravity • Geodesic effect • Evidence • Eddington experiment • Astronomy • GPS • Everett experiment Breakdown at quantum scales
III Skepticism from supernovas • Supernova • Huge implosion of massive star • Neutrinos released • Light delayed by debris • Supernova 1987a • Neutrinos detected • Ahead of light by 5 min Not by 5 years !
Many years for new result to be accepted Must be reproducible Must fit known experiments IV Skepticism in science If so Thomas Kuhn • Paradigm shift • Slow, gradual process (DJ) • Consensus process Compare: accelerating universe
The OPERA viewpoint ‘Despite the large significance of the measurement reported here and the stability of the analysis, the potentially great impact of the result motivates the continuation of our studies in order to investigate possible still unknown systematic effects that could explain the observed anomaly. We deliberately do not attempt any theoretical or phenomenological interpretation of the results’ ‘Up to half of the members of the OPERA project are opposed to immediately publishing the result in a peer-reviewed journal. They do not believe any known mistakes are being hidden by other members of the group, but are worried about the significant impact to physics of the results.’ Physics World
Scientific skepticism misunderstood Attributed to conservatism Role of evidence misunderstood ‘Balanced’ debate unweighted ‘Skepticism’ in the media Science journalism: news driven Bjorn Lomborg contrarian Climate ‘skepticism’ is not scientific
Extraordinary result Indirect measurement Contradicts theory Special and general relativity Contradicts experiment Particle experiments Astronomy experiments Extraordinary evidence? X Summary What if.... ? Further reading: ANTIMATTER
What if result stands? • Extra dimensions Shortcut? Doesn’t violate relativity • Unification theory 7 dimensions curled up? • High energy Lightest particles Doesn’t contradict previous results First evidence of string theory ?