Fashion: Jewelry
Alpha Pendant   (+14)  [vote for, against]
An eternal heartbeat

Sometimes life is little more than a series of disappointments. Moments are fleeting, meaningless. It would be erroneous to suggest that a mere pendant could make a difference, but an idea can be more than its physical manifestation. It can be a symbol, something eternal; an emotional anchor.

Exotic substances like polonium and americium exhibit alpha radiation. While deadly poisonous if swallowed, these materials are safe to handle as the alpha radiation is unable to penetrate skin, or even a few centimetres of air. The radiation consists of "heavy" particles, much heavier than other kinds of radiation.

Many people fear ionizing radiation, or more specifically, fear the concept of radiation. It is the ultimate threat: a toxin which you cannot see, hear, or smell. Pedantry over different types of radiation is irrelevant. To the ignorant, the invisible enemy is everywhere.

The Alpha Pendant contains a significant amount of radioactive americium. Beyond the visceral thrill of carrying a vial of poison around your neck, the americium serves a purpose.

The pendant consists of an evacuated glass cylinder, set in gold. Within the glass is a wheel of metal foil, mounted on the finest of needle bearings against jewelled supports. Every effort has been made to minimize friction of the wheel's rotation. Attached to the wheel are four paddles, and to each paddle a small disk of americium is attached on one side.

The alpha radiation carries momentum. The asymmetry of the paddles maximizes the effect. The power delivered is minuscule, but balanced against the inertia of the foil, the precision bearings, and the high vacuum it resides in, the resulting force is enough to rotate the assembly once per second.

The outer circumference of the wheel is partially coated in reflective silver, the remainder in absorptive black nanocrystals of gold. The pattern of reflective/absorptive coating is such that the reflected light, visible through the glass window on the pendant, creates the characteristic double-thump of a human heartbeat.

In essence, the pendant is a nuclear-powered trinket, both simpler and more intricate than a watch.

The mechanical heartbeat of the Alpha Pendant pumps no blood, but its silent pulse is a visible beacon of hope, a reminder that if we put our minds to it, it is possible to make something that lasts. With a half-life of 432 years, the americium-powered heartbeat will outlive your great grandchildren.
-- mitxela, Jun 13 2020

(?) Alpha Patent
If you ever want to file with this idea [pashute, Jun 14 2020]

Coat the inside with phosphorescent paint and it will glow in the dark too!
-- pocmloc, Jun 13 2020

Love it.

Make Americium Great Again!
-- 2 fries shy of a happy meal, Jun 13 2020

i want one with spinning paddles that look like tiny american flags. just make sure it's adequately shielded.
-- sninctown, Jun 13 2020

//The pattern of reflective/absorptive coating is such that the reflected light, visible through the glass window on the pendant, creates the characteristic double-thump of a human heartbeat.//

I just love this no matter what it is. The writing is so flowing and incredibly fluent that it's more like a poem than anything. Yes, yes, yes. +++++
-- blissmiss, Jun 13 2020


//Make Americium Great Again!// [marked-for-tagline]
-- FlyingToaster, Jun 14 2020

My mother was buried with her (working, to the best of my knowledge) pace maker.
-- pashute, Jun 14 2020

Crookes radiometer.
-- xenzag, Jun 14 2020

//trapped helium//

I'm uncomfortable to see those two words put together.
-- Voice, Jun 15 2020

You could vent the trapped helium through a one-way valve
-- pocmloc, Jun 15 2020

Thanks for the comments everyone.

Before posting this, I had a go at working out how much americium would be needed. The part I struggled to estimate was the friction of the bearing, I'm not sure what a reasonable guess for that would be.

You can buy a "StaticMaster" anti-static brush that contains 500uCi of polonium on amazon. The alpha particles have an energy of about 5MeV, so the power output is around 15uW. Not all of that will go into pushing the wheel around, but a quick search and stackoverflow answer suggest that a mechanical watch uses just over 10uW. So, I convinced myself that with enough americium, the thing would work.

I did consider the accumulation of helium. One point to note is that ordinary silicate glass is permeable to helium, so it would diffuse out over time. This also implies that by osmosis, helium and hydrogen would seep into the vial from the moment it was made. My gut feeling is that the effects will be insignificant compared to the mechanical bearing.
-- mitxela, Jun 16 2020

Very cool.
-- doctorremulac3, Jun 16 2020

// In essence, the pendant is a nuclear-powered trinket // Like the whole universe [+]
-- piluso, Jul 20 2020

Coud you wear one if you weren't in fact an alpha male?
-- RayfordSteele, Jul 20 2020

random, halfbakery