If such a 3-pronged molecule existed (but see my post below), then if you hold it with one uniquely identifiable arm pointing up and another uniquely identifiable arm pointing away, the third arm is uniquely pointing either L or R. Which gives you an unambiguous means to label L and R.
If your actual objection is “but which way is ‘up’?” then the answer for anybody on a planet is “up” is outwards in your gravity well and “down” is towards the center of your gravity well. The local gravity vector gives you an unambiguous local up / down. Towards / away is equally unambiguous.
Thank you. That kills my idea. And yes, I recall that SF short story although I don’t recall the author.
I think a corollary to your info would be that the actual L/R weak force asymmetry folks are talking about doesn’t lead to any chemistry-scale consequences. It’s lost in the sauce of lower-level particle physics.
Is it possible that a man stepping out of a time machine 800,000 years ago would observe that a majority of animals seemed to be left-handed? Is there a magnetic reason why a most humans and other species exhibit handedness? Since many (or most or all) species are predominantly right- or left-handed, there must be some biological advantage to handedness. In fact, in most species studied, the right-brain-left-brain dichotomy exists, with a strong preference within a species for consistency.
Australian marsupials show a strong left-handedness, which suggests that the observation of the apparent movement of the sun might be an evolutionary factor.
Wikipedia only lists humans and ground-dwelling macropode marsupials under handedness. Have you got any sources for the underlying “facts” for this wild speculation?
This is a very interesting point in relation to the OP question! Do you have a cite of some sort? I’m asking because I always thought humans were the one of the few, if not the only, animals with a clear and consistent dexterity and thus the only animals with a clear concept of difference between left and right…
You’re right that the direction of an electric current is not arbitrary, it can be communicated. (Though this still hinges on the assumption that your aliens are not made of antimatter.)
However, magnetic field is arbitrary, i.e. labeling the north and south poles of a magnet (or a planet) is arbitrary. Ampere’s right hand rule may look like it defines the direction, but if you redefine the direction (i.e. swap the definition of magnetic north and south), this just becomes a left-hand rule.
Don’t need them to be, but I am assuming “top” and “bottom” are definable in gravitic terms if nothing else. If we’re dealing with antimatter beings or space energy clouds, all bets are off.
N & S are arbitrary, I i know that. I’m thinking strictly in terms of : 'if you look along the same direction the electrons are flowing, then the lines of flux in the perpendicular plane are going clockwise. We define “left” as the direction the flux is flowing at the bottom, “right” as the direction it’s flowing at the top.
I’m assuming a certain degree of technical sophistication here, of course…
See my response above. I assume by “flux” you mean the direction of the magnetic field. This is arbitrary. What you are doing here is conveying the definition of the magnetic field direction to someone who already knows what right and left mean.
I thought this was the direction a positive charge would move in if introduced next to the charge-carrying wire? I’m happy to be wrong, though, it’s been decades since i was taught this sort of thing and i’ve never had to use it.
No, a magnetic field doesn’t do anything to a stationary charged particle. What it does is deflect the path of a moving charged particle, at right angles to the magnetic field and the direction of motion. To figure out which way the path is deflected, you use… the right hand rule.
So if you redefined the magnetic field direction, by replacing Ampere’s right-hand rule with the left-hand rule, everything still works. Because you’d use the same left-hand rule to figure out how charged particles behave in a magnetic field.
Roger Zelazny’s short story “Doorways in the Sand” also had a bit about reversing the steriochemistry, the main character absorbed an alien artifact. A fun read, the author started most every chapter with the hero is some preposterous situation and the rest of the chapter was about how he got there.
Are there asymmetrical allotropes or molecular forms that could be used to define left and right?
I don’t know how to even describe the incomplete memory I have about something involving the legs of insects and some substance found only on one side. That may not resolve the question in the OP but it’s driving me crazy trying to remember what that is and I’m not having any success searching online for it.
If, as the OP suggests, these alien critters already understand the concept of right and left, then it’s just a matter to translate the “words”. Simple enough to tell a German speaker that “right” means “recht”
Asimov, in one of his science essays (not fiction), conjectured that it is due to the asymmetry of the Weak Force that in turn caused the biological predominance of homochirality.
Ergo, there might also be a chance that our alien friends biology also has the same forms of handedness (L for amino acids, D for sugars).
Note that there has also been some evidence of handedness preferences in meteors. In addition to the Weak Force arguement, another has to with circular polarization. See the above link.
Excluding “scientific attributes” in this matter basically makes it a pointless question. It will always come down to some sort of scientific matter.