Steve Jurvetson

A blimp over San Francisco.

The massive airship you see in the video, flying over San Francisco is the Pathfinder 1, a state-of-the-art rigid airship built by LTA Research, a company backed by Google co-founder Sergey Brin. This historic aircraft is roughly 400 feet long, making it nearly twice the length of a Boeing 747 and the largest airship to take to the skies since the 1930s.

The Pathfinder 1 uses non-flammable helium for lift rather than hydrogen, and its structure is made of advanced carbon fiber and titanium tubing covered in a specialized synthetic skin. It is powered by twelve electric motors that allow it to take off and land vertically, while also maneuvering precisely through changing coastal winds.

The airship is currently undergoing a rigorous series of test flights out of its hangar at Moffett Field in Mountain View. Engineers are using these flights to evaluate its handling and stability over the San Francisco Bay, with the ultimate goal of developing zero-emission airships for humanitarian aid, disaster relief, and sustainable cargo transport.

[📹 thurber_shots] x.com/BladudX/status…

How to change your mind... with a number of new tools.
We hosted a lunch meeting with a couple of our favorite Stanford Profs: Nolan Williams (rapid TMS, ibogaine, nanoparticle drug-delivery to specific brain regions unlocked by focused ultrasound) and Karl Deisseroth (optogenetics, deep brain gene expression and ketamine).

Deisseroth is the pioneer of optogenetics, the mind-reading & writing tool that allows for individual neuron targeting and manipulation, and his new work looks at the effects of mind-altering drugs on brain function in detail.

For a sense of the power of his methods: he can take a pair of mice than were just mating happily, and with a flip of a switch, they become violent to each other. He made a mouse walk in an infinite left turn loop when a fiber optic is flipped on in the motor cortex (with no apparent awareness or distress at being controlled this way). He admits that he finds this capability “deeply disturbing.”

Another team selectively activated subsets of parenting behavior (like bringing wandering young back to the nest, or grooming behaviors). They can also probe three different sub-states of anxiety that we only experience as a bundle.

How does this work? Before the plant kingdom evolved chlorophyll to harvest energy from sunlight, the more ancient bacteria used rhodopsins in a membrane-bound proton-pump to do the same. The rhodopsins captured a swath of the sun’s spectrum, tilting the algae to the leftover parts of the spectrum not yet absorbed, and this is why plants are green. Karl introduced these bacterial light-triggered elements into neurons of interest using a viral vector to the brain. He can then trigger neuronal firing optically, as the rhodopsin pump supplements the ion channels in the neuron. He can also trigger reporter molecules from the bacterial world to read out brain activity as the brain is functioning.

So, for example, he has observed a 3 Hz cycling in the retrosplenial cortex of a mouse brain on ketamine, and he has been able to reproduce the effects with optogenetic stimulation to achieve similar effects. He has also found that the dissociative drugs (ketamine and PCP) allow for reflexes to pain (e.g., heat on paw or puff of air to eyes) to continue normally, while the protective cognitive reactions (licking the paws after heat or squinting in anticipation of the next puff) disappear, a disassociation of mind and body reflexes.

He is diving deeper into the brain to investigate how this works, finding that the various subregions of the thalamus are regulated by disassociative drugs by overpowering the voting circuits with a pulsing 3 Hz modulation of the ketamine-enhanced circuits. The other nodes in the thalamus are operating as before, but do not achieve as powerful a consensus. The thalamus regulates where we spend our attention and conscious focus, to avoid doing everything we might be tempted to do simultaneously, and thereby not really doing any of them well.

The implications of this level of understanding are enormous. The questions we can now ask using optogenetics will transform how we understand mental disorders and also call into question some deep philosophical questions surrounding consciousness and free will. It may also unveil the mysteries about how psychedelics operate in the brain, allowing us to optimize the use cases for testing in human clinical trials. Exciting work is going on with psilocybin for alcohol use disorder, extreme OCD and the eating disorders (which are also a disassociation of mind from body).

Also, “some patients do not disassociate on ketamine. From some anecdotal evidence, those tend to be the sociopaths.”

Disassociation naturally has a 10% incidence, and 70% among people with trauma. When in a state of induced disassociation (e.g., from ketamine), that 3 Hz rhythm occurs in a part of the Default Mode Network involved with coordinate transformations (aligning the 3D models for ego-centric and allocentric coordinates).

I find this fascinating in light of Jeff Hawkins’ work on the ubiquity of reference frames in cortical columns: Everything we perceive is a constructed reality, a cortical consensus from competing internal models resident in many cortical columns, the amalgam of 1000 brains. Those models are updated by data streaming from the senses. But our reality resides in the models.
Some of Deisseroth’s newest work saves and sequences the brain cells that stick to the deep-drain electrode needles, a core sample of genetic expression at different depths. These cells were routinely discarded, but now offer a new view into the workings of the brain.

• More on optogenetics: optogenetics.org at Stanford

• My prior post on @NolanRyWilliams and the remarkable results using a single dose of ibogaine to cure TBI disability (and depression, PTSD, anxiety, and addiction all in one go): x.com/FutureJurvetso…

Last weekend at Black Rock (BALLS 34), I flew my (near)-hypersonic homebuilt experimental 54mm rocket to Mach 4.96 (5372 fps)! To my knowledge, this is the fastest single-stage rocket ever flown and fully recovered by any amateur, among other records in student rocketry.

Secretary Pete Hegseth has announced that Elon Musk , along with Palmer Luckey and Newt Gingrich, will co-lead a new War Department effort to study the future of warfare.

The first meeting will be held today and a report will be submitted within 120 days. x.com/ThePatriotOasi…

@ambrosiaenergy just hit 2 MW of solar at our pilot plant. We broke ground Jan 4, completed the first 1 MW on Aug 17, and 2 MW on Sept 24.

Each solar panel we install with our ground mechanism now takes under 10 person-minutes to install, compared to the industry standard of ~120 person-minutes.[1] Our install time includes all amortized land clearing, road install, wiring, racking, and anchoring.
Everything we do is built in a factory, rolled out to the field, and snapped together.

Our innovative battery storage design also enables 24+ hour storage. That means we can deliver power to customers at 99% to 99.9% reliability, at competitive prices, built in 9-12 mo.  Next up: 30 MW of continuous power in 2027, then hundreds of MW after that.

We're a team of under 20 and hiring in Austin, El Paso, and Redwood City. Come build the fastest power plants in the US with us.

[1] docs.nlr.gov/docs/fy23osti/…

We just raised $25M in new funding led by Future Ventures (@VenturesVc), with @HyperplaneVC and @lakestarvc - bringing Modulate’s total funding to $60 million.

Building the next phase of audio-native AI: more models, more developers, more of the stack that actually understands voice.

Where we stand today:

- Ranked #1 on Hugging Face for deepfake detection and transcription
- 600M+ hours of audio analyzed
- 10M+ hours analyzed every month

A foundational layer of the AI stack is getting more powerful. More soon.

Ceci n'est pas une tweet!

The Twitter HQ illuminated bird logo just arrived, 63" tall and proud.

Environmental impact analysis should compare to common practice. When we rejected nuclear for 50 years, we furthered coal. Environmental concerns about nuclear ended up devastating the environment. We made a mistake.

Today, it's metals mining for the energy transition.
A vs $TMC

⌚ Watching you watching me

I love skeleton watches that show the inner clockwork and those with unique takes on timekeeping. Here is another eclectic batch, from L to R:

1) The white Omega x Swatch Moonshine Gold. It is the first and only watch that shows the phases of Earth as seen by an astronaut on the moon (soon to be relevant again). The Earth goes through phases, in reverse of the moon phases. So, when you have a new Moon, you have a “full Earth” as seen on the watch face here. And for an observer at Moon Base Alpha, the Earth will always be in roughly the same spot in the sky, neither rising nor setting… and the dark part of Earth will have the faint illumination of Moonshine (just as the dark part of the moon gets a bit of Earthshine making it visible during a new moon phase). The watch is made of a light bioceramic with an homage to Apollo 10’s Snoopy, and each watch has a unique moon “snowflake” design.

2) Martin Braun EOS: A unique design that shows the time of sunrise and sunset. For a mechanical watch, this is particularly tricky, using two crossed titanium hands on cams customized for the latitude of the owner (the googly eyes at the bottom). The sunset/sunrise dial range also varies by latitude (with little change at the equator), and the feature will not be accurate for travel from home.

3) Ulysse Nardin Blast Free Wheel Maillechort. Various assemblages, like the flying constant force tourbillon and power reserve indicator float like islands on the face, connected by a hidden gear train below. Like several of their watches, the design required the use of MEMS silicon escapement. It is serial #2 of 50, and the first sold in America. Made of Maillechort, a rare copper alloy, white gold and a sapphire glass box (which looks very cool from the sides).

4) Ulysse Nardin Freak. It was my first love in unique complicated watches. The watch mechanism is built into the minute hand which drives a small gear at the tip of the hand that runs along the inner circumference of the dial, rotating it around and driving the hour hand below. Sleek design with no crowns protruding from the side. It was my 20th anniversary gift at DFJ. Serial #13.

5) Breguet Tradition Chronograph, a skeleton with a symmetric design front and back for the watch + stopwatch. Founded in 1775, Breuget invented the self-winding watch and was a favorite of Marie Antoinette and Napoleon, who had four and brought them into battle.

Next Row:

6) BVLGARI Octo Finissimo, super thin skeleton in titanium. It’s probably my lightest watch. I bought it with a friend while travelling overseas… Watches can serve as memorable mementos in time.

7) Carl F. Bucherer. My first skeleton, also thin, purchased in the late 80’s and I remember negotiating a discount from the store in the Stanford Shopping Center. Bucherer AG was acquired by Rolex in 2023.

8) Vacheron Constantin Régulateur Chronometer, my first from them. I have always admired the elegance of their design. The minute hand is central, hours on top, and the dual-time face (left) is easily adjustable by the push-button for travel to different time zones.

9) TAG Heuer Monaco Chronograph. I like the pink flair in this edition, and it also serves as a travel memory. It’s a skeleton watch, but with black-on-black titanium, it does not show well in the photo.

10) Harry Winston Perpetual Calendar. It has a moon phase and retrograde calendar that adjusts month and day for leap years. I am not sure about the art deco design though.

More in the post below.

19 operators signed up for initial deployments starting later this year.

20% downlink spectral efficiency demonstrated

Multiple AI-native app partners including
@pulsone, @ZaiNarTech, and @deepsignl

Radio Networks that can sense, plan, and, act. AI is here for radio networks and @Nokia and @Nvidia are bringing it to the world first.