Monopola
Dirac's Monopole Physics
Size guide S–5XL · inches
Monopola carries a single magnetic pole, field lines bursting out like a sunburst. If she exists anywhere, every charge in the universe has to fall in line.
The Physics
Paul Dirac showed that if even one magnetic monopole exists, quantum mechanics forces all electric charge to come in whole-number steps. That would explain why charge is quantised. The monopole needs a singular line, the Dirac string, which cannot be seen if the condition holds.
e g = n ħ c / 2 (Gaussian units, n = 0, ±1, ±2, …)
- e: electric charge
- g: magnetic charge of the monopole
- n: integer
- ħ: reduced Planck constant
- c: speed of light (all in Gaussian units, as printed)
Dirac published it in 1931. B. Cabrera (Stanford) recorded one candidate event on 14 Feb 1982 in 151 days of running; it was never repeated.
Honest caveat: No magnetic monopole has ever been confirmed. The monopole field shown on the back is hypothetical.
On the shirt
Front: Monopola, the pixel-art character, with the title. Back: the Dirac quantisation condition, the hypothetical monopole field, the Cabrera candidate and both papers. Printed on a unisex tee.
Shipping calculated at checkout by destinationMade to order, ships in 2–5 business days
Details
Size & fitS–5XL
Unisex heavy cotton (Gildan 5000), classic fit.
| Size | Width | Length | Sleeve |
|---|---|---|---|
| S | 18 | 28 | 15.1 |
| M | 20 | 29 | 16.5 |
| L | 22 | 30 | 18 |
| XL | 24 | 31 | 19.5 |
| 2XL | 26 | 32 | 21 |
| 3XL | 28 | 33 | 22.4 |
| 4XL | 30 | 34 | 23.7 |
| 5XL | 32 | 35 | 25 |
For scale: size M is 20 in (50.80 cm) wide, about 3.143 × 1034 Planck lengths (lP = 1.616255 × 10−35 m). A tape measure is quicker.
Measurements in inches, ±1.5 in tolerance.
ShippingBy destination
Shipping calculated at checkout by destination. Printed to order for you.
Returns & replacements21 days
Every item is printed to order, so we can’t accept returns or exchanges for change of mind, or if you ordered the wrong size or colour.
Print defect, misprint, damage or the wrong item? We’ll send a free replacement, or a refund if you prefer. Report it within 21 days of delivery with a photo; no need to send it back.
Field notes
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