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The Big Bang, the LHC and the God Particle Cormac O’Raifeartaigh (WIT) Faster than the speed of light Was Einstein wrong? Cormac O’Raifeartaigh (WIT)

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Presentation on theme: "The Big Bang, the LHC and the God Particle Cormac O’Raifeartaigh (WIT) Faster than the speed of light Was Einstein wrong? Cormac O’Raifeartaigh (WIT)"— Presentation transcript:

1 The Big Bang, the LHC and the God Particle Cormac O’Raifeartaigh (WIT) Faster than the speed of light Was Einstein wrong? Cormac O’Raifeartaigh (WIT)

2 Overview IThe experiment What, why, how IIRelativity (special) Theory and experiment III Relativity (general) Theory and experiment IV Skepticism in science Coda: what if..?

3 The OPERA experiment Result: early by 60 nanoseconds Beam of neutrinos at CERN Detector under Gran Sasso Distance of 732 km Time of flight 2.43 ms 0.003% faster than light in vacuum! Highly respected group

4 Neutrinos Suggested by Pauli (1930) Conservation of energy Zero charge, ‘zero’ mass Weak interaction Skepticism (non-physicists) Detected in 1956

5 Neutrinos Tiny mass (non-zero?) Dark matter? The solar neutrino paradox Gran Sasso experiment Three different types Neutrino oscillation Change of flavour

6 Standard Model neutrino = lighter cousin of electron

7 The OPERA experiment

8 OPERA: the numbers Measurement of distance (GPS) 732 km +/- 20 cm Time of flight +/- 10ns 2.43006 +/- 0.00001 ms Velocity = distance/time Δv/v = 2.5 x 10 -5 (25 ppm) Note: proton pulse 10 μs long (10,000 ns) 60 ns early (18 m??)

9 OPERA Snags 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/time Need to direct beam at the moon Systematic error ?

10 II The theory of relativity (special) Laws of physics identical for observers in uniform motion Speed of light in vacuum a fundamental constant Length contraction Time dilation Mass increase E = mc 2 Implications for bodies at high speed

11 Early experiments Kaufmann, Bucherer Particle accelerators Length contraction Time dilation Mass increase Modern particle accelerators Speed limit Particle creation E = mc 2 Evidence for relativity

12 CERN (Geneva) energy increase velocity increase? K.E = 1/2mv 2 mass increases

13 Time dilation: muons v = 3 x 10 8 m/s t = 2.2 x 10 -6 s (lifetime) d = 660m Moving clocks run slow Many muons detected at ground level d = 10 km ? Muons created in upper atmosphere Vampire muon

14 Relativity ‘skepticism’ Extraordinary concept Counter-intuitive Only observable at tremendous speeds Only observable for subatomic particles Simple maths Time and distance calculations Personalization Confusion of discovery and justification Compare: evolution, climate science Speed of light plays role of infinity Dr Al Kelly ‘Einstein wrong’

15 III The general theory of relativity Gravity = curvature of space and time Laws of physics identical for all observers Speed of light in vacuum a universal constant Principle of equivalence New view of gravity Revolution Cosmological implications Matter warps space and time General Relativity (1915)

16 General relativity (experiment) Predictions Bending of starlight by sun Black holes Expanding universe Geodesic effect Time dilation by gravity Evidence Eddington experiment Astronomy Cosmology (big bang) Everett experiment GPS Breakdown at quantum scales

17 Relativity and GPS Signal from satellite compare time received to transmitted synchronized clocks Convert time to distance x speed of radiowaves Assumes constancy of speed of light Triangulation using 4 sources accurate to within 5 metres

18 GPS: a relativistic correction Motion of satellite (SR) Clocks slow by 7 μs/day Reduced gravity field (GR) Clocks fast by 45 μs/day Satellite clocks fast by 38 μs/ day Well-known correction to GPS OPERA - new correction? (18m?) Synchronization of satellite/earth clocks

19 Skepticism from astronomy Supernova Huge implosion of massive star Neutrinos released Light delayed Supernova 1987a Neutrinos detected Ahead of light by 3 hours Not by 5 years !

20 IV Skepticism in science Many years for new result to be accepted Must be reproducible Must fit known experiments Paradigm shift Slow, gradual process (DJ) Consensus process If so Compare: accelerating universe Thomas Kuhn

21 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

22 Science in the media Scientific skepticism misunderstood Attributed to conservatism Role of evidence misunderstood ‘Balanced’ debate unweighted Climate ‘skepticism’ is not scientific Science journalism: news driven Bjorn Lomborg

23 Summary Extraordinary result Indirect measurement Contradicts theory Special and general relativity Contradicts experiment Particle experiments Astronomy experiments Extraordinary evidence? X But what if.... ?

24 What if result stands? First evidence of string theory ? Extra dimensions Shortcut? Doesn’t violate relativity Unified field theory 7 dimensions curled up? High energy Lightest particles Doesn’t contradict previous results Further reading: ANTIMATTER

25 H


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