Physicist George Ellis Knocks Physicists for Knocking Philosophy, Falsification, Free Will | Cross-Check, Scientific American Blog Network: Physics experiments are approaching the highest energies it will ever be possible to test by any collider experiment, both for financial and technical reasons. We can’t build a collider bigger than the surface of the Earth. Thus our ability to test high energy physics – and hence structures on the smallest physical scales – is approaching its limits. Astronomical observations at all wavelengths are now probing the most distant cosmological events that will ever be “seeable” by any kinds of radiation whatever, because of visual horizons for each form of radiation.
It’s rather like the situation as regards exploring the Earth: once
upon a time we had only fragmentary knowledge of what is there. Then we
obtained a global picture of the Earth’s surface, including detailed
satellite images of the entire land mass. Once you have seen it all, you
have seen it all; apart from finer and finer details, there is nothing
more to find. You might respond, But we can’t see to the bottom of the
oceans. However, we do indeed now have quite good maps of the ocean
floor too, through various sounding techniques. This is similar to the
way we have seen right back to the last scattering surface in the early
universe at a redshift of 1200 (the analogue of seeing the entire
surface of the Earth from space) with satellites such as COBE, WMAP, and
Planck, and also (indirectly) to the time of emission of gravitational waves by Bicep2 (the analogue of seeing to the bottom of the ocean). We’ll sort out that controversy in the next couple of years.
So what we can see at the largest and smallest scales is approaching
what will ever be possible, except for refining the details.