When Deepinder Goyal appeared on a recent podcast wearing a small metallic device stuck near his temple, the internet took notice. The clip quickly revived discussion around his “brain flow” experiment
and the gadget he calls Temple. This time, the pushback came sharp and direct from a doctor at AIIMS Delhi.
Dr Suvrankar Datta, an AI researcher and radiologist with clinical training from AIIMS, dismissed the device outright, calling it a “fancy toy” built for billionaires with money to burn.
postcast is fine, but what is this thing he's wearing?? pic.twitter.com/Oku16Oku1R
— priyanshu.sol (@priyanshudotsol) January 4, 2026
What Goyal Says The Temple Device Does
Back in November 2025, Goyal shared what he described as the “Gravity Aging Hypothesis.” The idea suggested that gravity could gradually reduce blood flow to the brain over a lifetime, potentially playing a role in ageing. Around the same time, images of him wearing a gold-coloured gadget near his right temple began circulating online.
Goyal later confirmed the device was experimental and designed to measure brain blood flow with precision. He said he had been wearing it himself for nearly a year as part of his personal research. In December 2025, he hinted that Temple could eventually be made available to the public, sparking curiosity and skepticism in equal measure.
I’m not sharing this as the CEO of Eternal, but as a fellow human, curious enough to follow a strange thread. A thread I can’t keep with myself any longer.
It’s open-source, backed by science, and shared with you as part of our common quest for scientific progress on human… pic.twitter.com/q2q3tRj3Jd
— Deepinder Goyal (@deepigoyal) November 15, 2025
‘Zero Scientific Standing,’ Says AIIMS Doctor
Dr Datta didn’t mince words. Responding to a photo of Goyal wearing the Temple device, he wrote on X:
“As a physician-scientist and one of the earliest researchers in India in Arterial Stiffness and Pulse Wave Velocity (2017) which predicts cardiovascular mortality, I can assure you that this device currently has 0 scientific standing as a useful device.”
He followed that up with a blunt warning aimed at potential buyers. “Do not waste your hard earned money to buy fancy toys billionaires can afford to waste money on. If you are one, then go ahead,” he said.
As a physician-scientist and one of the earliest researchers in India in Arterial Stiffness and Pulse Wave Velocity (2017) which predicts cardiovascular mortality, I can assure you that this device currently has 0 scientific standing as a useful device and do not waste your hard… https://t.co/pm0pxGRycd
— Dr. Datta M.D. (AIIMS Delhi) (@DrDatta_AIIMS) January 4, 2026
Why He Says The Science Doesn’t Hold Up
In a follow-up post, Dr Datta explained that his criticism was rooted in evidence, not opinion. According to him, any device claiming to measure brain blood flow in a way that predicts ageing or mortality needs years of rigorous, peer-reviewed research.
He stressed that cfPWV, or carotid-femoral pulse wave velocity, remains the only scientifically validated marker for predicting cardiovascular mortality.
“And you cannot just use the temporal artery as a surrogate because they aren’t reflective and have many confounding factors,” he said, arguing that measurements taken near the temple are unreliable and easily distorted.
Also, mai hawa mein baat nahi karta, guys!
We have tried variety of stuff in 2018, including trying to use AI for interpretation.
On the basis of our research we applied for Indian Innovation Growth Programme, and went to the Finals.
Only cfPWV is a marker which can truly… pic.twitter.com/cacM1A94P1
— Dr. Datta M.D. (AIIMS Delhi) (@DrDatta_AIIMS) January 4, 2026
When asked directly whether Goyal’s gravity-based ageing idea had scientific backing, Dr Datta was clear. “As of now there is no scientific basis,” he replied, cautioning against promoting ideas before they are properly proven.




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