The Most Distant Galaxies: Forever Blurred
Some pesky scientists are predicting that the nature of the universe might soon introduce a fundamental limit to the resolution of deep space galaxies using our next generation of telescopes.
Using a telescope to resolve objects in deep space is not an easy task. Just looking up into the night sky with your naked eyes can give you a clue to that fact. We all know that stars twinkle (astronomers call it scintillation). But why does this happen? It’s all because of our wonderful and horrible atmosphere.
The inherent turbulence in our atmosphere is caused by the countless temperature and density fluctuations. These variations easily refract the pinpoint of light coming from stars causing it to zig-zag a bit on the last leg of its journey to our retinas. We see this as twinkling. Planets don’t twinkle nearly as much because their light doesn’t emanate from a pinpoint but from a disk of light. Any zig-zagging of one part of its light is often cancelled-out by the opposite zig-zagging of another part of its light. The good news is that we can deal with this distortion in multiple ways:
- Putting the telescope above the atmosphere like Hubble removes all traces of twinkling.
- Using adaptive optics to synchronize the shape of the lens to the turbulent atmosphere so most of the twinkling is cancelled-out
So we’re good now right? We can just put bigger and better telescopes in space or on the ground to get better and better pictures?
A new study by Scientists at the International Astronomical Union General Assembly predicts that there is a “fundamental resolution limit” to the universe that will forever prevent us from seeing distant galaxies at the highest level of detail that optics otherwise would allow.
This distorting effect is possibly embedded in the universe at its most fundamental quantum level, way down at length scales approaching 10 to the minus 35 meters. This lilliputian regime is known as the Planck scale. It is obviously difficult to figure out what the hell’s going on at this scale since directly probing it would require energies one quintillion times greater than what we can muster in our best particle accelerators. Even if we could probe it with light at sufficiently small wavelengths, it would be so energetic and massive (this is the Planck energy scale) that the light could actually turn into a black hole and swallow any information it could impart to us.
Yet there are some fairly widely accepted theories about some of what’s going on here. For one, quantum theory predicts that pairs of virtual particles are continually popping into existence in this “foamy” realm and mutually annihilating each other. These particles, even if it’s for the briefest amount of time, have energy and therefore mass. This mass, minuscule as it is, would necessarily have to warp space by a certain amount. This then is the crux of the image resolution problem of the universe.
Any photons from distant galaxies would have to traverse such vast tracts of space that all these tiny bends in space-time or ‘phase perturbations” could add up to blur the image much like our atmosphere does. Unfortunately, getting around this is not as easy as lofting Hubble into space or employing adaptive optics. In fact, it’s probably impossible to counter.
This hasn’t happened yet since none of our telescopic images are resolved enough to notice. The next generation of scopes however like the James Webb Space Telescope could potentially hit this wall of maximum resolution for deep space objects.
This is especially frustrating for me since I love imagining far future technology like telescopes as big as solar systems. These would give us quite lovely and incredibly detailed images of galaxies, stars, and planets relatively nearby. To think that tools of this size could still be fundamentally and severely limited for the most distant and ancient galaxies kinda pisses me off.
Oh well. We’ll just have to go there ourselves and take a real close look 😉
p.s. I know we can’t do that
Images Credit: Nasa/Hubble