This will take at least 10 years. In this case, you must be
an expert in both Biology and Physics.
2. Ask an expert.
This just changes the question from "Is the claim believable?" to
"Is this person an expert?" How do you know?
3. It all comes down to trust.
You can't check every fact for yourself. Eventually, you need to
trust someone. If you are skeptical about everything and trust no one,
you will be paralyzed. If you are credulous about everything and
trust everyone, you are going to lose money, your health, and possibly
your life.
4. Look at the motivations of the promoters and
detractors
Beware of experts that (a) have motives that stem from strong beliefs or ideologies that demand compliance to
the science / pseudoscience or (b) want to sell you something.