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The brain’s lifeline, its network of blood vessels, is like a tree, says Mathieu Pernot, deputy director of the Physics for Medicine Paris Lab. The trunk begins in the neck with the carotid arteries, a pair of broad channels that then split into branches that climb into the various lobes of the brain. These channels fork endlessly into a web of tiny vessels that form a kind of canopy. The narrowest of these vessels are only wide enough for a single red blood cell to pass through, and in one important sense these vessels are akin to the tree’s leaves.
“When you want to look at pathology, usually you don’t see the sickness in the tree, but in the leaves,” Pernot says. (You can identify Dutch Elm Disease when the tree’s leaves yellow and wilt.) Just like leaves, the tiniest blood vessels in the brain often register changes in neuron and synapse activity first, including illness, such as new growth in a cancerous brain tumor.1, 2 But only in the past decade or so have we developed the technology to detect these microscopic changes in blood flow: It’s called ultrafast ultrasound.
> The images show activity in deep regions of the brain where past imaging couldn’t reach.
Standard ultrasound is already popular in clinical imaging given that it is minimally invasive, low-cost, portable, and can generate images in real time.3 But until now, it has rarely been used to image the brain. That’s partly because the skull gets in the way—bone tends to scatter ultrasound waves—and the technology is too slow to detect blood flow in the smaller arteries that support most brain function. Neurologists have mostly used it in niche applications: to examine newborns, whose skulls have gaps between the bone plates, or to guide surgeons in some brain surgeries, where part of the skull is typically removed. Neuroscience researchers have also used it to study functional differences between the two hemispheres of the brain, based on imaging of the major cerebral arteries, by positioning the device over the temporal bone window, the thinnest area of the skull.
But ultrafast ultrasound is exponentially faster, more powerful, and more spatially sensitive than standard ultrasound: It can produce many thousands of detailed high-resolution images per second.3 If conventional ultrasound is like peeking through a keyhole, ultrafast ultrasound “opens the whole door,” says Peifeng Song, who researches ultrasound techniques at the University of Illinois Urbana-Champaign. Neuroscientists say it could not only help doctors make much earlier diagnoses of debilitating brain diseases, such as brain cancer or Alzheimer’s, but could also aid neuroscientists working with animal models in solving major research questions and accelerate the development of non-invasive brain-machine interfaces, such as robotic limbs.
“If you talk about neuroscience and how the brain works, there’s a lot of unknowns,” Song says. “It’s the wild west.” Ultrafast ultrasound could trace brain signaling with great precision, documenting how circuits and groups of cells interact as the brain performs functions from perception to decision-making.
Functional ultrasound imaging works by the process of echolocation, the same process bats use to navigate. Too high pitched for humans to hear, ultrasound waves collide with tissues or cells in the body and reflect out. Their echoes can then be captured and used to calculate the locations and velocities of blood cells. The frequencies of the returning ultrasound waves reveal where blood is flowing, supplying oxygen and glucose to brain regions that are working especially hard, or conversely, which parts of the brain are not receiving the blood and nutrients they need. These images allow researchers and clinicians to get a sense of what parts of the brain are active—for example, regions responsible for decision-making—or which ones might be at risk of damage.4
In the last decade or so, advances in computer processing power have allowed researchers to transform ultrasound technology. Instead of emitting individual beams, these newer ultrasound systems send out a series of plane waves—an array of ultrasound beams that together form a plane—that hit their target at different angles. The resulting images are composites that are multiple orders of magnitude sharper than conventional ultrasound, MRI, or CT scans, without the trade-offs faced by other imaging methods. MRI machines, for example, demand hugely powerful and expensive magnets to improve their resolution.5 The new forms of ultrasound can also work up to 100 times faster than conventional ultrasound tools, which is especially useful during medical emergencies, when time is of the essence. Such speeds allow ultrasound to track seizures as they happen, Pernot says.
“Even just a few years ago, that type of data throughput would have just been mountainous,” says Sumner Norman, a postdoc at Caltech. “So you wouldn’t have been able to do much with it.” But as computer capacity caught up with the demand, ultrafast ultrasound became more feasible. In Song’s lab, their 3-D ultrasound imaging requires around 10 terabytes of data to fully image the brain of each lab animal in 3-D—the same amount it would take to stream Netflix in standard definition for 10,000 hours.
**Bubbles in the Brain:** Ultrasound localization microscopy takes high resolution images of blood flow in the brain by bouncing ultrasound waves off of microscopic gas bubbles injected into the blood. *Credit: Junjie Yao’s lab at Duke University.*
Now that researchers have the computing power to create such high-speed, fine-grained images, they can also track the movement of cells over time. [Research](https://www.nature.com/articles/s41592-022-01549-5) published in August by the lab of Mickael Tanter of PSL Research University in France depicted activity throughout the rat brain at a microscopic level.6 The images show activity in deep regions of the brain where light-based imaging can’t reach, and in stunning detail—much finer resolution than an MRI or CT scan. The pictures showed activity from second to second down to a scale of a few thousands of a millimeter.
In humans, ultrasound researchers are finding creative ways to work around the impediment of the skull. Fabienne Perren at the University of Geneva and colleagues, including Tanter, used a [contrast agent](https://neurocenter-unige.ch/humain-brain-vascularisation-revealed-by-ultrafast-ultrasounds-at-a-microscopic-level-for-the-first-time/)—microbubbles of gas injected into patients’ blood.7 Some waves still collide with the skull and scatter, but the ones that make it through are more likely to reflect back out when they bounce off the bubbles. Where a CT scan showed only a blob, ultrasound imaging allowed the team to zoom in until they could pinpoint the turbulence inside a bulging blood vessel. Tanter’s lab has also sent ultrasound signals through the gaps between newborns’ skull plates to record [brain activity during seizures and sleep](https://www.science.org/doi/full/10.1126/scitranslmed.aah6756).8
Scientists can also remove a small piece of the skull to facilitate working with ultrasound. Working with monkeys, Norman and his colleagues replaced a domino-sized piece of the skull with an ultrasound device. The images of activity in a part of the brain that plans movement revealed when a monkey intended to move an arm. In fact, they could predict the direction of the movement [about 89 percent of the time](https://www.sciencedirect.com/science/article/pii/S0896627321001513?dgcid=coauthor).9 This is comparable to methods that implant electrodes in the scalp, which have been reported to accurately predict direction of movement roughly 70 to 90 percent of the time.
> You can’t wheel an MRI machine onto a battlefield. But you can take a handheld device.
But ultrasound imaging does a better job detecting activity deep within the brain, which is harder for electrodes on the scalp to detect. Electrodes are also far more invasive and can cause tissue damage. And the rapidly accelerating capacities of ultrasound will bring improvements, researchers expect. These findings were published last year in *Neuron* and could pave the way for robotic limbs that translate thought into action: Ultrasound imaging could read brain activity, revealing how a person wants to move their hand to the left, and that data could be fed into a computer that controls a robotic arm, for instance. “We’re already moving toward humans,” Norman says.
Ultrafast ultrasound could also assist surgeons, who often remove pieces of bone before operating anyway. Zin Khaing, an assistant professor of neurological surgery at the University of Washington, is [now testing](https://reporter.nih.gov/search/Woq41Wvmu0mJxWqTQ3QCog/project-details/10179815) enhanced ultrasound on spinal surgery patients. “If I were to get injured today,” she says, “you would do a CT or an X-ray.” Perhaps an MRI, too. But these only produce anatomical images. “It just shows you where all the bits and pieces are, and what’s squishing onto your soft spinal cord tissue,” Khaing says. Imaging that tracks blood flow is not part of the protocol.
In her pilot clinical trial, ultrafast ultrasound is used in the operating room so doctors can follow the movement of blood. Zhaing is aiming to map what tissue still has blood flow, so that doctors can know what will be salvageable, and what areas are still swollen—perhaps where the surgeon should relieve pressure. She hopes ultrasound could guide surgery even in geographies with fewer resources. “You can’t wheel an MRI machine to a war situation, right? But you can have a handheld ultrasound device,” she says. Plus, she imagines ultrasound technology that’s even easier to use than a probe: something more like a bandaid. MIT researchers have already developed [thin ultrasound stickers](https://www.science.org/doi/10.1126/science.abo2542) that can monitor organs over time without a doctor holding an ultrasound wand.10
At the Physics for Medicine Paris Lab, Pernot is hopeful that scientists will be able to correct for the skull’s effects on ultrasound waves. In the same way that researchers can compensate for a flaw in the lens of a telescope, they could also use an algorithm to adjust for the way the skull scatters ultrasound signals, he says. X-rays that map the exact geometry of a skull can guide a model of exactly how the skull distorts ultrasound waves, says Junjie Yao, a researcher at Duke who develops technology that uses both ultrasound and light-based imaging. And that model can be used to correct ultrasound images so they appear undistorted, as though there weren’t any skull there at all. “I wouldn’t say it’s impossible to overcome the hurdle of the skull, but it will be an engineering challenge,” Yao adds.
Ultrasound imaging is still evolving rapidly. “New ideas are popping up every day,” Yao says. Norman was impressed by how quickly his work progressed—in only a few years, he moved from small animal tests to large animal experiments and showed the potential of ultrasound to read brain activity that could feed into a computer.9 “It was incredible how quickly it moved. Usually when you start a new technology, you’re in for a decades-long slog to make it work,” he says. But when computer processing accelerated, the benefits of ultrafast ultrasound became clear. Now researchers can follow rivulets of blood deep into the brain. “We are going to have an imaging technique to go into another world,” Tanter says. 
*Research into the use of contrast agents in ultrafast ultrasound by Fabienne Perren is funded by the Bertarelli Foundation.*
*Lead image: Paul Craft / Shutterstock*
**References**
1\. Guyon, J., Chapouly, C., Andrique, L., Bikfalvi, A., & Daubon, T. The normal and brain tumor vasculature: Morphological and functional characteristics and therapeutic targeting. *Frontiers in Physiology***12**, 622615 (2021).
2\. Baloyannis, S. Brain capillaries in Alzheimer’s disease. *Hellenic Journal of Nuclear Medicine***1:152** (2015).
3\. Deffieux, T., Demené, C., & Tanter, M. Functional ultrasound imaging: A new imaging modality for neuroscience. *Neuroscience***474**, 110-121 (2021).
4\. Montaldo, G., Urban, A., & Macé, E. Functional ultrasound neuroimaging. *Annual Review of Neuroscience***45**, 491-513 (2022).
5\. Nowogrodzki, A. The world’s strongest MRI machines are pushing human imaging to new limits. *Nature* (2018).
Take gravity, add quantum mechanics, stir. What do you get? Just maybe, a holographic cosmos.
Credit...Leonardo Santamaria
- Published Oct. 10, 2022Updated Oct. 11, 2022, 12:01 p.m. ET
For the last century the biggest bar fight in science has been between Albert Einstein and himself.
On one side is the Einstein who in 1915 conceived general relativity, which describes gravity as the warping of space-time by matter and energy. That theory predicted that space-time could bend, expand, rip, quiver like a bowl of Jell-O and disappear into those bottomless pits of nothingness known as black holes.
On the other side is the Einstein who, starting in 1905, laid the foundation for quantum mechanics, the nonintuitive rules that inject randomness into the world — rules that Einstein never accepted. According to quantum mechanics, a subatomic particle like an electron can be anywhere and everywhere at once, and a cat can be both alive and dead until it is observed. God doesn’t play dice, Einstein often complained.
Gravity rules outer space, shaping galaxies and indeed the whole universe, whereas quantum mechanics rules inner space, the arena of atoms and elementary particles. The two realms long seemed to have nothing to do with each other; this left scientists ill-equipped to understand what happens in an extreme situation like a black hole or the beginning of the universe.
But a blizzard of research in the last decade on the inner lives of black holes has revealed unexpected connections between the two views of the cosmos. The implications are mind-bending, including the possibility that our three-dimensional universe — and we ourselves — may be holograms, like the ghostly anti-counterfeiting images that appear on some credit cards and drivers licenses. In this version of the cosmos, there is no difference between here and there, cause and effect, inside and outside or perhaps even then and now; household cats can be conjured in empty space. We can all be Dr. Strange.
“It may be too strong to say that gravity and quantum mechanics are exactly the same thing,” Leonard Susskind of Stanford University [wrote in a paper in 2017](https://arxiv.org/abs/1708.03040). “But those of us who are paying attention may already sense that the two are inseparable, and that neither makes sense without the other.”
That insight, Dr. Susskind and his colleagues hope, could lead to a theory that combines gravity and quantum mechanics — quantum gravity — and perhaps explains how the universe began.
## Einstein vs. Einstein
The schism between the two Einsteins entered the spotlight in 1935, when the physicist faced off against himself in a pair of scholarly papers.
In one paper, Einstein and Nathan Rosen showed that general relativity predicted that black holes (which were not yet known by that name) could form in pairs connected by shortcuts through space-time, called Einstein-Rosen bridges — “wormholes.” In the imaginations of science fiction writers, you could jump into one black hole and pop out of the other.
In the other paper, Einstein, Rosen and another physicist, Boris Podolsky, tried to pull the rug out from quantum mechanics by exposing a seeming logical inconsistency. They [pointed out](http://www.nytimes.com/2005/12/27/science/27eins.html "Times article on quantum entanglement.") that, according to the uncertainty principle of quantum physics, a pair of particles once associated would be eternally connected, even if they were light-years apart. Measuring a property of one particle — its direction of spin, say — would instantaneously affect the measurement of its mate. If these photons were flipped coins and one came up heads, the other invariably would be found out to be tails.
To Einstein this proposition was obviously ludicrous, and he dismissed it as “spooky action at a distance.” But today physicists call it “entanglement,” and lab experiments confirm its reality every day. Last week the [Nobel Prize in Physics](https://www.nytimes.com/2022/10/04/science/nobel-prize-physics-winner.html) was awarded to a trio of physicists whose experiments over the years had demonstrated the reality of this “spooky action.”
The physicist N. David Mermin of Cornell University once called such quantum weirdness “[the closest thing we have to magic](https://www.nytimes.com/2006/01/10/health/new-tests-of-einsteins-spooky-reality.html).”
As Daniel Kabat, a physics professor at Lehman College in New York, explained it, “We’re used to thinking that information about an object — say, that a glass is half-full — is somehow contained within the object. Entanglement means this isn’t correct. Entangled objects don’t have an independent existence with definite properties of their own. Instead they only exist in relation to other objects.”
Einstein probably never dreamed that the two 1935 papers had anything in common, Dr. Susskind said recently. But Dr. Susskind and other physicists now speculate that wormholes and spooky action are two aspects of the same magic and, as such, are the key to resolving an array of cosmic paradoxes.
## Throwing Dice in the Dark
To astronomers, black holes are dark monsters with gravity so strong that they can consume stars, wreck galaxies and imprison even light. At the edge of a black hole, time seems to stop. At a black hole’s center, matter shrinks to infinite density and the known laws of physics break down. But to physicists bent on explicating those fundamental laws, black holes are a Coney Island of mysteries and imagination.
In 1974 the cosmologist Stephen Hawking astonished the scientific world with a heroic calculation showing that, to his own surprise, black holes were neither truly black nor eternal, when quantum effects were added to the picture. Over eons, a black hole would leak energy and subatomic particles, shrink, grow increasingly hot and finally explode. In the process, all the mass that had fallen into the black hole over the ages would be returned to the outer universe as a random fizz of particles and radiation.
This might sound like good news, a kind of cosmic resurrection. But it was a potential catastrophe for physics. A core tenet of science holds that information is never lost; billiard balls might scatter every which way on a pool table, but in principle it is always possible to rewind the tape to determine where they were in the past or predict their positions in the future, even if they drop into a black hole.
But if Hawking were correct, the particles radiating from a black hole were random, a meaningless thermal noise stripped of the details of whatever has fallen in. If a cat fell in, most of its information — name, color, temperament — would be unrecoverable, effectively lost from history. It would be as if you opened your safe deposit box and found that your birth certificate and your passport had disappeared. As Hawking phrased it in 1976: “God not only plays dice, he sometimes throws them where they can’t be seen.”
His declaration triggered a 40-year war of ideas. “This can’t be right,” Dr. Susskind, who became Hawking’s biggest adversary in the subsequent debate, thought to himself when first hearing about Hawking’s claim. “I didn’t know what to make out of it.”
Image
Credit...Leonardo Santamaria
## Encoding Reality
A potential solution came to Dr. Susskind one day in 1993 as he was walking through a physics building on campus. There in the hallway he saw a display of a hologram of a young woman.
A hologram is basically a three-dimensional image — a teapot, a cat, Princess Leia — made entirely of light. It is created by illuminating the original (real) object with a laser and recording the patterns of reflected light on a photographic plate. When the plate is later illuminated, a three-dimensional image of the object springs into view at the center.
“‘Hey, here’s a situation where it looks as if information is kind of reproduced in two different ways,’” Dr. Susskind recalled thinking. On the one hand, there is a visible object that “looked real,” he said. “And on the other hand, there’s the same information coded on the film surrounding the hologram. Up close, it just looks like a little bunch of scratches and a highly complex encoding.”
The right combinations of scratches on that film, Dr. Susskind realized, could make anything emerge into three dimensions. Then he thought: What if a black hole was actually a hologram, with the event horizon serving as the “film,” encoding what was inside? It was “a nutty idea, a cool idea,” he recalled.
Across the Atlantic, the same nutty idea had occurred to the Dutch physicist, Gerardus ’t Hooft, a Nobel laureate at Utrecht University in the Netherlands.
According to Einstein’s general relativity, the information content of a black hole or any three-dimensional space — your living room, say, or the whole universe — was limited to the number of bits that could be encoded on an imaginary surface surrounding it. That space was measured in pixels 10⁻³³ centimeters on a side — the smallest unit of space, known as the Planck length.
With data pixels so small, this amounted to quadrillions of megabytes per square centimeter — a stupendous amount of information, but not an infinite amount. Trying to cram too much information into any region would cause it to exceed a limit decreed by Jacob Bekenstein, then a Princeton graduate student and Hawking’s rival, and cause it to collapse into a black hole.
“[This is what we found out about Nature’s bookkeeping system](https://arxiv.org/pdf/hep-th/0003004.pdf),” Dr. ’t Hooft wrote in 1993. “The data can be written onto a surface, and the pen with which the data are written has a finite size.”
## The Soup-Can Universe
The cosmos-as-holograph idea found its fullest expression a few years later, in 1997. Juan Maldacena, a theorist at the Institute for Advanced Study in Princeton, N.J., used new ideas from string theory — the speculative “theory of everything” that portrays subatomic particles as vibrating strings — to create a mathematical model of the entire universe as a hologram.
In his formulation, all the information about what happens inside some volume of space is encoded as quantum fields on the surface of the region’s boundary.
Dr. Maldacena’s universe is often portrayed as a can of soup: Galaxies, black holes, gravity, stars and the rest, including us, are the soup inside, and the information describing them resides on the outside, like a label. Think of it as gravity in a can. The inside and outside of the can — the “bulk” and the “boundary” — are complementary descriptions of the same phenomena.
Since the fields on the surface of the soup can obey quantum rules about preserving information, the gravitational fields inside the can must also preserve information. In such a picture, “[there is no room for information loss](https://www.nytimes.com/2004/07/22/world/about-those-fearsome-black-holes-never-mind.html),” Dr. Maldacena said at a conference in 2004.
Hawking conceded: Gravity was not the great eraser after all.
“In other words, the universe makes sense,” Dr. Susskind said in an interview.
“It’s completely crazy,” he added, in reference to the holographic universe. “You could imagine in a laboratory, in a sufficiently advanced laboratory, a large sphere — let’s say, a hollow sphere of a specially tailored material — to be made of silicon and other things, with some kind of appropriate quantum fields inscribed on it.” Then you could conduct experiments, he said: Tap on the sphere, interact with it, then wait for answers from the entities inside.
“On the other hand, you could open up that shell and you would find nothing in it,” he added. As for us entities inside: “We don’t read the hologram, we are the hologram.”
Image
Credit...Leonardo Santamaria
## Wormholes, wormholes everywhere
Our actual universe, unlike Dr. Maldacena’s mathematical model, has no boundary, no outer limit. Nonetheless, for physicists, his universe became a proof of principle that gravity and quantum mechanics were compatible and offered a font of clues to how our actual universe works.
But, Dr. Maldacena noted recently, his model did not explain how information manages to escape a black hole intact or how Hawking’s calculation in 1974 went wrong.
Don Page, a former student of Hawking now at the University of Alberta, took a different approach in the 1990s. Suppose, he said, that information is conserved when a black hole evaporates. If so, then a black hole does not spit out particles as randomly as Hawking had thought. The radiation would start out as random, but as time went on, the particles being emitted would become more and more correlated with those that had come out earlier, essentially filling the gaps in the missing information. After billions and billions of years all the hidden information would have emerged.
In quantum terms, this explanation required any particles now escaping the black hole to be entangled with the particles that had leaked out earlier. But this presented a problem. Those newly emitted particles were already entangled with their mates that had already fallen into the black hole, running afoul of quantum rules mandating that particles be entangled only in pairs. Dr. Page’s information-transmission scheme could only work if the particles inside the black hole were somehow the same as the particles that were now outside.
How could that be? The inside and outside of the black hole were connected by wormholes, the shortcuts through space and time proposed by Einstein and Rosen in 1935.
In 2012 Drs. Maldacena and Susskind proposed a formal truce between the two warring Einsteins. They proposed that spooky entanglement and wormholes were two faces of the same phenomenon. As they put it, employing the initials of the authors of those two 1935 papers, Einstein and Rosen in one and Einstein, Podolsky and Rosen in the other: “ER = EPR.”
The implication is that, in some strange sense, the outside of a black hole was the same as the inside, like a Klein bottle that has only one side.
How could information be in two places at once? Like much of quantum physics, the question boggles the mind, like the notion that light can be a wave or a particle depending on how the measurement is made.
What matters is that, if the interior and exterior of a black hole were connected by wormholes, information could flow through them in either direction, in or out, according to John Preskill, a Caltech physicist and quantum computing expert.
“We ought to be able to influence the interior of one of these black holes by ‘tickling’ its radiation, and thereby sending a message to the inside of the black hole,” he said [in a 2017 interview with Quanta](https://www.quantamagazine.org/newfound-wormhole-allows-information-to-escape-black-holes-20171023/). He added, “It sounds crazy.”
Ahmed Almheiri, a physicist at N.Y.U. Abu Dhabi, noted recently that by manipulating radiation that had escaped a black hole, he could create a cat inside that black hole. “I can do something with the particles radiating from the black hole, and suddenly a cat is going to appear in the black hole,” he said.
He added, “We all have to get used to this.”
The metaphysical turmoil came to a head in 2019. That year two groups of theorists made detailed calculations showing that information leaking through wormholes would match the pattern predicted by Dr. Page. One paper was by Geoff Penington, now at the University of California, Berkeley. And the other was by Netta Engelhardt of M.I.T.; [Don Marolf](https://web.physics.ucsb.edu/~marolf/) of the University of California, Santa Barbara; [Henry Maxfield](https://inspirehep.net/authors/1272287), now at Stanford University; and Dr. Almheiri. The two groups published their papers on the same day.
“And so the final moral of the story is, if your theory of gravity includes wormholes, then you get information coming out,” Dr. Penington said. “If it doesn’t include wormholes, then presumably you don’t get information coming out.”
He added, “Hawking didn’t include wormholes, and we are including wormholes.”
Not everybody has signed on to this theory. And testing it is a challenge, since particle accelerators will probably never be powerful enough to produce black holes in the lab for study, although several groups of experimenters hope to simulate black holes and wormholes in quantum computers.
And even if this physics turns out to be accurate, Dr. Mermin’s magic does have an important limit: Neither wormholes nor entanglement can transmit a message, much less a human, faster than the speed of light. So much for time travel. The weirdness only becomes apparent after the fact, when two scientists compare their observations and discover that they match — a process that involves classical physics, which obeys the speed limit set by Einstein.
As Dr. Susskind likes to say, “You can’t make that cat hop out of a black hole faster than the speed of light.”
@ -176,7 +176,8 @@ The following Apps require a manual backup:
- [x] :cloud: [[Storage and Syncing|Storage & Sync]]: Backup Standard Notes (PC) %%done_del%% 🔁 every 3 months on the 1st Friday 📅 2022-10-07 ✅ 2022-10-06
- [x] :cloud: [[Storage and Syncing|Storage & Sync]]: Backup Standard Notes (PC) %%done_del%% 🔁 every 3 months on the 1st Friday 📅 2022-10-07 ✅ 2022-10-06
- [ ] Backup [[Storage and Syncing#Instructions for Anchor|Anchor Wallet]] %%done_del%% 🔁 every 3 months on the 1st Thursday 📅 2023-01-05
- [ ] Backup [[Storage and Syncing#Instructions for Anchor|Anchor Wallet]] %%done_del%% 🔁 every 3 months on the 1st Thursday 📅 2023-01-05
- [x] Backup [[Storage and Syncing#Instructions for Anchor|Anchor Wallet]] %%done_del%% 🔁 every 3 months on the 1st Thursday 📅 2022-10-06 ✅ 2022-10-03
- [x] Backup [[Storage and Syncing#Instructions for Anchor|Anchor Wallet]] %%done_del%% 🔁 every 3 months on the 1st Thursday 📅 2022-10-06 ✅ 2022-10-03
- [ ] :iphone: Backup [[Storage and Syncing#Instructions for iPhone|iPhone]] %%done_del%% 🔁 every 3 months on the 2nd Tuesday 📅 2022-10-11
- [ ] :iphone: Backup [[Storage and Syncing#Instructions for iPhone|iPhone]] %%done_del%% 🔁 every 3 months on the 2nd Tuesday 📅 2023-01-10
- [x] :iphone: Backup [[Storage and Syncing#Instructions for iPhone|iPhone]] %%done_del%% 🔁 every 3 months on the 2nd Tuesday 📅 2022-10-11 ✅ 2022-10-11
- [ ] :floppy_disk: Backup [[Storage and Syncing#Instructions for FV|Folder Vault]] %%done_del%% 🔁 every 3 months on the 1st Friday 📅 2023-01-06
- [ ] :floppy_disk: Backup [[Storage and Syncing#Instructions for FV|Folder Vault]] %%done_del%% 🔁 every 3 months on the 1st Friday 📅 2023-01-06
- [x] :floppy_disk: Backup [[Storage and Syncing#Instructions for FV|Folder Vault]] %%done_del%% 🔁 every 3 months on the 1st Friday 📅 2022-10-07 ✅ 2022-10-06
- [x] :floppy_disk: Backup [[Storage and Syncing#Instructions for FV|Folder Vault]] %%done_del%% 🔁 every 3 months on the 1st Friday 📅 2022-10-07 ✅ 2022-10-06
- [ ] :cloud: [[Storage and Syncing|Storage & Sync]]: Backup Volumes to [[Sync|Sync.com]] %%done_del%% 🔁 every 3 months on the 2nd Monday 📅 2022-12-12
- [ ] :cloud: [[Storage and Syncing|Storage & Sync]]: Backup Volumes to [[Sync|Sync.com]] %%done_del%% 🔁 every 3 months on the 2nd Monday 📅 2022-12-12
iOS
2 years ago