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Single Idea 21138

[filed under theme 27. Natural Reality / B. Modern Physics / 4. Standard Model / e. Protons ]

Full Idea

The proton (938.3 MeV) is lighter than the neutron (939.6 MeV) and does not decay, but the heavier neutron can change into a proton by emitting an electron. (If you gather a bucketful of neutrons, after ten minutes only half of them would be left).

Gist of Idea

Neutrons are slightly heavier than protons, and decay into them by emitting an electron

Source

New Scientist writers (Why the Universe Exists [2017], 01)

Book Ref

New Scientist writers: 'Why the Universe Exists' [John Murray 2017], p.5

A Reaction

Protons are more or less eternal, but some theories have them decaying after billions of years. Smashing protons together is a popular pastime for physicists.

Related Idea

Idea 21141 Neutrinos were proposed as the missing energy in neutron beta decay [New Sci.]

The 41 ideas from 'Why the Universe Exists'

21142 Classifying hadrons revealed two symmetry patterns, produced by three basic elements [New Sci.]
21143 Quarks in threes can build hadrons with spin ½ or with spin 3/2 [New Sci.]
21140 Spin is a built-in ration of angular momentum [New Sci.]
21144 Top, bottom, charm and strange quarks quickly decay into up and down [New Sci.]
21138 Neutrons are slightly heavier than protons, and decay into them by emitting an electron [New Sci.]
21141 Neutrinos were proposed as the missing energy in neutron beta decay [New Sci.]
21158 Fermions, with spin ½, are antisocial, and cannot share quantum states [New Sci.]
21145 The four fundamental forces (gravity, electromagnetism, weak and strong) are the effects of particles [New Sci.]
21157 Particles are spread out, with wave-like properties, and higher energy shortens the wavelength [New Sci.]
21153 The weak force explains beta decay, and the change of type by quarks and leptons [New Sci.]
21156 The weak force particles are heavy, so the force has a short range [New Sci.]
21155 Photons have zero rest mass, so virtual photons have infinite range [New Sci.]
21149 Quarks have red, green or blue colour charge (akin to electric charge) [New Sci.]
21159 Supersymmetry has extra heavy bosons and heavy fermions [New Sci.]
21160 The Higgs field means even low energy space is not empty [New Sci.]
21154 Three particles enable the weak force: W+ and W- are charged, and Z° is not [New Sci.]
21150 Three different colours of quark (as in the proton) can cancel out to give no colour [New Sci.]
21146 Electrons move fast, so are subject to special relativity [New Sci.]
21148 The strong force is repulsive at short distances, strong at medium, and fades at long [New Sci.]
21152 The strong force binds quarks tight, and the nucleus more weakly [New Sci.]
21151 Gluons, the particles carrying the strong force, interact because of their colour charge [New Sci.]
21147 Quantum electrodynamics incorporates special relativity and quantum mechanics [New Sci.]
21161 In the standard model all the fundamental force fields merge at extremely high energies [New Sci.]
21162 Only supersymmetry offers to incorporate gravity into the scheme [New Sci.]
21164 Why do the charges of the very different proton and electron perfectly match up? [New Sci.]
21165 Spin is akin to rotation, and is easily measured in a magnetic field [New Sci.]
21163 The mass of protons and neutrinos is mostly binding energy, not the quarks [New Sci.]
21168 Gravitional mass turns out to be the same as inertial mass [New Sci.]
21167 Gravity is unusual, in that it always attracts and never repels [New Sci.]
21166 Standard antineutrinos have opposite spin and opposite lepton number [New Sci.]
21170 The Standard Model cannot explain dark energy, survival of matter, gravity, or force strength [New Sci.]
21169 Only neutrinos spin anticlockwise [New Sci.]
21171 The symmetry of unified electromagnetic and weak forces was broken by the Higgs field [New Sci.]
21172 The evidence for supersymmetry keeps failing to appear [New Sci.]
21173 Supersymmetry says particles and superpartners were unities, but then split [New Sci.]
21174 Dark matter must have mass, to produce gravity, and no electric charge, to not reflect light [New Sci.]
21175 String theory might be tested by colliding strings to make bigger 'stringballs' [New Sci.]
21177 String theory offers a quantum theory of gravity, by describing the graviton [New Sci.]
21178 String theory is now part of 11-dimensional M-Theory, involving p-branes [New Sci.]
21176 In the Big Bang general relativity fails, because gravity is too powerful [New Sci.]
21179 Supersymmetric string theory can be expressed using loop quantum gravity [New Sci.]