Tape measures and scales, calendars and speedometers are just a few of the tools we use to measure out our lives — inch by inch, pound by pound, day by day. We’ve got measuring down to a science, one that divides the universe into units and standards. But how do you measure things that are really hard to pin down — when there’s no unit or standard? On this episode, we dig into the quest to quantify those elusive measures. We hear about the growing field of ecoacoustics, which uses sound to study the biodiversity and the health of ecosystems; we learn why measuring metabolism requires locking people into sealed chambers; and we hear about innovative ideas for measuring everything from happiness to infinity.

Also heard on this week’s episode:

• Our metabolisms are related to a whole host of health issues — but how exactly do they work? Reporter Jad Sleiman finds out with a visit to a metabolic chamber in Bethesda, Md. — a special kind of laboratory designed to measure all the energy going into and coming out of a body.
• Reporter Matthew Schneeman chats with two mathematicians from Cornell University about the mind-bending concept of infinity.
• Della Duncan and Robert Raymond of the “Upstream” podcast tell us about how Bhutan has come up with its own way of measuring the country’s happiness.
• Political candidates are talking about their ideas for health care reform — but how do we measure the cost? Dan Gorenstein, host of the podcast “Tradeoffs” joins us to discuss a tool that could measure those costs.
• Theoretical physicist Sylvester James Gates Jr. joins us to talk about his new book “Proving Einstein Right: The Daring Expeditions that Changed How We Look at the Universe.” It describes the grueling quest of astronomers to provide a crucial measurement proving Einstein’s theories.