“I trust in nature for the stable laws of beauty and utility. Spring shall plant and autumn garner to the end of time.” –Robert Browning
You’ve heard it said often that one thing remains true no matter what we discuss: that this, too, shall pass. The stars will eventually burn out, the galaxies will be driven apart, gravitational interactions will unbind everything, and even collapsed entities like black holes will decay away. But at a fundamental level, is that actually the case for matter itself?
We’ve observed plenty of particle interactions and radioactive decays, but particles like the proton (and many other atomic combinations) appear to be truly stable. If that’s the case, we can set limits on how long the proton lifetime is, and constrain exotic hypotheses like Grand Unified Theories as a result!