IndexQuantumTee

Lenta

17 Metres per Second Physics

$29.99 USD
$29.99 USD
Sale Sold out
Size
Color

Size guide S–5XL · inches

Lenta walks a beam of light on a leash, slowed to bicycle speed.

The Physics

Electromagnetically induced transparency uses a control laser to make an opaque atomic cloud transparent over a narrow range of colours. Across that window the refractive index changes extremely steeply, so a light pulse's group velocity drops enormously.

v_g = c / (n + ω dn/dω)

  • v_g: group velocity (m/s)
  • c: speed of light (m/s)
  • n: refractive index (dimensionless)
  • ω: angular frequency (rad/s)

In 1999 Hau, Harris, Dutton and Behroozi slowed light to 17 m/s in ultracold sodium, about 18 million times slower than in vacuum; in 2001 light was stopped.

On the shirt

Front: Lenta, the pixel-art character, with the title. Back: the group velocity formula, the EIT window, the 1999 result and the 2001 follow-up. 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.

SizeWidthLengthSleeve
S182815.1
M202916.5
L223018
XL243119.5
2XL263221
3XL283322.4
4XL303423.7
5XL323525

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.

Delivery times & where we ship

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.

Full refund & replacement policy

Field notes

View all
1 3
View all