WILLIAM ANDREGG USHERS me into the cluttered workshop of his startup Fathom Computing and gently lifts the lid from a bulky black box. Inside, green light glows faintly from a collection of lenses, brackets, and cables that resemble an exploded telescope. It’s a prototype computer that processes data using light, not electricity, and it’s learning to recognize handwritten digits. In other experiments the device learned to generate sentences in text.
Right now, this embryonic optical computer is good, not great: on its best run it read 90 percent of scrawled numbers correctly. But Andregg, who cofounded Fathom late in 2014 with his brother Michael, sees it as a breakthrough. “We opened the champagne when it was only at about 30 percent,” he says with a laugh.
Andregg claims this is the first time such complex machine-learning software has been trained using circuits that pulse with laser light, not electricity. The company is working to shrink its exploded telescope, which covers a few square feet of workbench, to fit into a standard cloud server. Fathom hopes the technology will become one of the shovels of the artificial-intelligence gold rush.
Tech companies, particularly large cloud providers like Amazon and Microsoft, spend heavily on computer chips to power machine-learning algorithms. The current AI-crazed moment began when researchers found that chips marketed for graphics were well-suited to power so-called artificial neural networks for tasks such as recognizing speech or images. The stock price of leading graphics-chip supplier Nvidia has grown more than 10-fold in the past three years, and Google and many other companies are now making or developing specialized machine-learning chips of their own.
Fathom’s founders are betting this hunger for more powerful machine learning will outstrip the capabilities of purely electronic computers. “Optics has fundamental advantages over electronics that no amount of design will overcome,” says William Andregg. He and his brother’s 11-person company is backed by Playground Global, the venture firm led by Andy Rubin, who coinvented the Android operating system now owned by Google.
Fathom operates out of Playground’s combined offices and workshops in Palo Alto, California. The facility, which true to its name also boasts a slide popular with Andregg’s 18-month-old daughter, previously hosted Nervana, the startup acquired by Intel in 2016 to form the heart of the chip giant’s AI hardware strategy.
You’re already reaping the benefits of using light instead of electricity to work with data. Telecommunications companies move our web pages and selfies over long distances by shooting lasers down optical fiber, because light signals travel much farther, using a fraction of the energy, than electrical pulses in a metal cable. A single cable can house many parallel streams of data at once, carried by light of different colors.
Using light to crunch data, as well as transport it, should also offer significant performance gains. Light inside optical circuits travels more or less for free. By contrast, electrical signals must battle resistance, producing waste heat. A combination of capacity gains and energy savings could be tempting to companies running big machine-learning projects. A single experiment at Google, for example, can now use hundreds of powerful graphics chips for solid weeks at a time, according to some of the firm’s research papers.
(sumber: Fathom Computer)