It’s that kind of an afternoon. Finished up one project, don’t feel much like starting another. Spring rain outside so instead of walking to Al’s for coffee I take the elevator down to Pizza Eddie’s on 2. Looks like other folks have the same feeling. “Afternoon, all. What’s the current topic of conversation?”

“Well, Sy, it started out as Star Wars versus Star Trek but then Jim said he could care less and Susan said that meant he did care and he said no, he’s ambivalent and she said that still meant he cared, and—”

“I get it, Eddie. Susan, why does ‘ambivalent‘ mean Jim cares?”

“Chemistry, Sy. ‘Valence‘ means ‘bonding‘ and ‘ambi-‘ means ‘both‘ so ‘ambi‑valent‘ means ‘bonded to both‘.”

“But Susan, ambidextrous means able to use both hands, not unable to use either hand. I want to say I don’t particularly like or dislike either one.”

“It’s like trying to decide between fire ants or hornets. You could say ‘No‑win,’ right?”

“No, that’s not it, either, Eddie. That’s ‘everybody loses.’ I’m smack in the middle.”

“Sounds like absolute neutrality. Hard to get there.”

“Don’t look at Chemistry. If I take an acid solution and add just enough base to get to neutral pH, there’s still tenth‑micromolar concentrations of acid and base in there. I guess we could call that ambivalent.”

“Neutrality’s hard for humans and chemicals, yeah, but that’s where the Universe is.”

“Why do you say that, Jim?”

“Because we’ve got proof right in front of us. Look, planets and stars and people exist as distinct objects, right? They’re not a finely-divided mist.”

“So?”

“So if the Universe were not exactly electrically neutral, then opposite charges repelling would split everything apart.”
 ”Wait, nothing would have a chance to form in the first place.”
   ”Wait, couldn’t you have lumps of like 99 positives and 100 negatives or whatever that just cancel out?”

“Eddie, when you say ‘cancel out’ you’re still talking about being absolutely neutral at the lump level. It’s like this table salt that has positive sodium ions and negative chlorides but the crystals are neutral or we’d get sparks when I pour some out like this.”
 ”Hey, don’t waste the salt. Costs money.”

“I still think it’s weird how all electrons have the same charge and it’s exactly the same as the proton charge. Protons are made of quarks, right, and electrons aren’t. So how can you take three of something and have that add up to exactly one of something different?”

“I can give you Feynman and Wheeler’s answer to part of that, Susan. The electron has an anti‑partner, the positron, which is exactly like the electron in every way except it has the opposite charge. When electron and positron meet they annihilate to produce a burst of high‑energy photons. But there’s a flip side — high‑energy photons sometimes interact to make an electron‑positron pair. Feynman and Wheeler were both jokers. They suggested that a positron could be an electron traveling backward in time. Wheeler said, ‘Maybe they’re all the same electron,’ zig‑zagging across eternity. But that doesn’t account for the quarks. A proton has two up‑quarks, each with a charge of negative ²/₃ electron, and one down‑quark with a charge of positive ¹/₃ electron. Add ’em up — you exactly neutralize one electron. Fun, huh?”

“Fun, Jim, but I’m a chemist. On a two-pan balance I can weigh out equal quantities of molasses and rock dust but I don’t expect them to interact with any simple mathematical relationship. Why should the quark’s charge be any exact multiple or divisor of the electron’s? And why is the electron charge the size it is instead of some other number?”

“Well, there you’ve got me. The quantum chromodynamics Standard Model has been amazingly successful for quantitative predictions, but not so good for explaining things outside of its own terms. The math lays out the relationship between quark and electron charge, but doesn’t give us a physical ‘why.’ The theory has 19 ‘adjustable constants’ but no particular reason why they should have the specific values that fit the observations. Also, the theory doesn’t include gravity. It’s a little embarrassing.”

“Sounds like you’re ambivalent about the theory.”

~~ Rich Olcott