Landauer Limit Demonstrated

Scientists show that a 50-year-old principle limiting future CMOS computing is real: Erasing information gives off heat

4 min read

7 March 2012—Physicists in Europe have experimentally demonstrated, for the first time, that a theoretical principle limiting modern-day computing is real.

In 1961, Rolf Landauer posited that the act of erasing a bit of information gives off an amount of heat related to the temperature and Boltzmann’s constant—a total of 3 x 10-21 joules at room temperature. Among other things, the theory has been used to address the famous problem of Maxwell’s Demon, a thought experiment that suggested a minute monster could create energy for free by sorting particles by their speed, in apparent violation of the laws of thermodynamics. Prior to 1982, when IBM’s Charles Bennett applied Landauer’s theory to the problem, the thinking was that the demon’s act of making measurements produced heat, eliminating the violation. But Bennett argued that heat was produced because the demon had to erase a bit of information in its memory in order to sort each particle.

Keep Reading ↓Show less

This article is for IEEE members only. Join IEEE to access our full archive.

Join the world’s largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum’s articles, podcasts, and special reports. Learn more →

If you're already an IEEE member, please sign in to continue reading.

Membership includes:

  • Get unlimited access to IEEE Spectrum content
  • Follow your favorite topics to create a personalized feed of IEEE Spectrum content
  • Save Spectrum articles to read later
  • Network with other technology professionals
  • Establish a professional profile
  • Create a group to share and collaborate on projects
  • Discover IEEE events and activities
  • Join and participate in discussions

The Spectacular Collapse of CryptoKitties, the First Big Blockchain Game

A cautionary tale of NFTs, Ethereum, and cryptocurrency security

8 min read
Mountains and cresting waves made of cartoon cats and large green coins.
Frank Stockton

On 4 September 2018, someone known only as Rabono bought an angry cartoon cat named Dragon for 600 ether—an amount of Ethereum cryptocurrency worth about US $170,000 at the time, or $745,000 at the cryptocurrency’s value in July 2022.

It was by far the highest transaction yet for a nonfungible token (NFT), the then-new concept of a unique digital asset. And it was a headline-grabbing opportunity for CryptoKitties, the world’s first blockchain gaming hit. But the sky-high transaction obscured a more difficult truth: CryptoKitties was dying, and it had been for some time.

Keep Reading ↓Show less