Hossenfelder Rebuffs Harvard String Theory 'Dark Dimension' Claims

String Theory Predicts Testable “Dark Dimension,” Physicists Say — Sabine Hossenfelder

Sabine Hossenfelder

Claims that a micrometer-scale extra dimension makes string theory testable merely shift theoretical goalposts and amount to institutionalized pseudoscience.

AI-assisted summary of String Theory Predicts Testable “Dark Dimension,” Physicists Say — original source. Check the original for full context.

Source published:

Key ideas

  • Harvard theoretical physicists led by Cumrun Vafa have proposed a "dark dimension" within string theory, suggesting a single extra spatial dimension compactified at roughly the micrometer scale to unify dark matter and dynamic dark energy. (0:00)
  • The model posits that gravitons leaking into the extra dimension acquire an effective mass that manifests as dark matter, predicting deviations from Newton's inverse-square law at approximately 10 micrometers—just beyond the current 30-micrometer experimental limit. (2:04)
  • Sabine Hossenfelder criticizes the proposal as moving the goalposts and "institutionalized pseudoscience," arguing that discovering an extra dimension would not prove string theory and that theorists will simply shrink the scale if near-future experiments yield null results. (4:00)

Detailed notes

## Background Published on YouTube by physicist Sabine Hossenfelder on September 6, 2026, this video responds to a report in The Economist claiming that string theory has finally become testable. According to the video description, Hossenfelder examines the claim that an extra dimension of space might be large enough to detect in a tabletop experiment and offers a sharply contrasting interpretation of the situation.

## TL;DR A Harvard research group led by Cumrun Vafa recently proposed that string theory can simultaneously address dark energy and dark matter via a "dark dimension"—one extra spatial dimension compactified at roughly the micrometer scale rather than the minuscule Planck scale. In this model, gravitons leaking into the extra dimension behave as massive dark matter particles and cause Newton's inverse-square law of gravity to break down at around 10 micrometers, conveniently just beyond the 30-micrometer threshold tested by current tabletop experiments. Sabine Hossenfelder dismantles this excitement as "institutionalized pseudoscience," arguing that the parameters are conjectured rather than derived and that discovering an extra dimension would only prove the existence of an extra dimension, not string theory. Ultimately, she frames the proposal as a classic example of theoretical physicists perpetually moving the goalposts just out of experimental reach to generate media hype.

## Atmosphere & style The presentation blends lucid, accessible physics exposition with Hossenfelder's signature deadpan wit and biting skepticism. What begins as a calm, methodical walkthrough of braneworlds and gravitons steadily builds into an exasperated, no-nonsense takedown of academic hype and uncritical science journalism. Watching it feels like getting a sobering reality check from an insider who is thoroughly exhausted by moving goalposts, before the mood softens into a pragmatic reflection on science education at the close.

## Bulletin - [00:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=0s) Harvard theoretical physicists led by Cumrun Vafa have proposed a "dark dimension" within string theory, suggesting a single extra spatial dimension compactified at roughly the micrometer scale to unify dark matter and dynamic dark energy. - [02:04](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=124s) The model posits that gravitons leaking into the extra dimension acquire an effective mass that manifests as dark matter, predicting deviations from Newton's inverse-square law at approximately 10 micrometers—just beyond the current 30-micrometer experimental limit. - [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) Sabine Hossenfelder criticizes the proposal as moving the goalposts and "institutionalized pseudoscience," arguing that discovering an extra dimension would not prove string theory and that theorists will simply shrink the scale if near-future experiments yield null results.

## Key takeaways - [00:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=0s) String theory has suffered from decades of untestability due to a landscape of roughly 10^500 vacuum configurations, none of which have conclusively yielded the Standard Model. - [00:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=0s) Following a 2018 theoretical argument that dark energy must vary over time, theorists capitalized on recent cosmological hints of dynamic dark energy to advance new string models. - [00:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=0s) The "dark dimension" hypothesis modifies typical compactification models by postulating that five extra dimensions remain microscopic while one is compactified at around a micrometer. - [02:04](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=124s) Under this braneworld framework, Standard Model particles like quarks and electrons are restricted to a 3D slice, whereas gravitons can freely propagate into the higher-dimensional bulk. - [02:04](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=124s) Gravitons traveling into the micrometer-scale dimension acquire an effective mass from a 3D perspective, calibrated to explain cosmic dark matter. - [02:04](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=124s) Compact extra dimensions alter gravitational behavior at short scales, causing departures from Newton's inverse-square law below the compactification radius. - [02:04](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=124s) Precision tabletop tests using torsion balances and cantilevers have confirmed Newtonian gravity down to 30 micrometers, placing the dark dimension's 10-micrometer prediction right past current empirical bounds. - [02:04](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=124s) Existing observational datasets from the Planck satellite and ground telescopes have not shown cosmological signatures supporting the dark dimension model. - [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) Theoretical physics frequently enters a cycle of pitching models placed just beyond current experimental reach to popular outlets, only to alter parameters after null results. - [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) Empirical confirmation of an extra spatial dimension would validate extra dimensions generally, rather than proving string theory or quantum gravity. - [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) Hossenfelder characterizes the practice of continually adjusting unproven theoretical parameters to sustain funding and headlines as institutionalized pseudoscience.

## Detailed walkthrough ### [00:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=0s) The Promise of the "Dark Dimension"

String theory has notoriously spent decades stranded in untestability, but a report in *The Economist* announced that this might finally be changing. Proponents are claiming that the framework has generated a genuinely testable prediction involving what they call a "dark dimension"—a phrase Sabine Hossenfelder jokes is "not a joke about the present state of academia," but rather an effort to simultaneously resolve dark matter and dark energy using string theory. Originally conceived as an all-encompassing theory of everything that would explain the particles of the Standard Model and their gravitational interactions, string theory ran into a mathematical quagmire: it permits an estimated $10^{500}$ distinct solutions, known as the string theory landscape, within which physicists have yet to identify a single configuration that cleanly reproduces the Standard Model.

Despite this impasse, string theorists remain convinced of their approach and have shifted tactics over the past decade. In 2018, theoretical physicists argued that within string theory, dark energy could not be an unchanging cosmological constant; it would necessarily vary with time. When observational hints from cosmological surveys over the past two years suggested that dark energy might indeed evolve over time, the Harvard research group led by Cumrun Vafa moved to push the hypothesis even further.

To build on this concept, Vafa's team reconsidered the extra spatial dimensions required by string theory. While standard models require six extra spatial dimensions that are traditionally assumed to be curled up into radii far too minuscule to ever probe experimentally, this group proposed a radical departure: what if five remain microscopic, but one extra dimension is compactified at a comparatively macroscopic scale—somewhere around a single micrometer?

- **The Landscape Problem:** An estimated $10^{500}$ vacuum states exist in the string theory landscape, none of which have been conclusively matched to our universe's Standard Model. - **Dynamic Dark Energy:** A 2018 proposal from string theorists argued that dark energy must be time-dependent rather than static, aligning with recent tentative observational hints. - **The Extra Dimension Twist:** Instead of hiding all six extra dimensions at the near-infinitesimal Planck scale, the proposal posits that a single dimension is rolled up at roughly the micrometer scale.

---

[02:04](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=124s) Massive Gravitons and Tabletop Gravity Tests

The physical mechanism of this "dark dimension" relies on a braneworld scenario. Standard Model particles such as electrons and quarks are trapped on a three-dimensional spatial slice—our familiar universe—while gravity is free to propagate across all spatial dimensions. Because string theory is fundamentally a quantum theory of gravity, the gravitational field is mediated by quanta called gravitons. Gravitons that escape our 3D slice and propagate into the compactified extra dimension acquire an effective mass from our perspective. The Harvard group proposes that these massive gravitons are precisely what constitutes cosmic dark matter. Calibrating the extra dimension's radius to a few micrometers produces a dark matter candidate that roughly matches astronomical observations.

Crucially, an extra dimension of this scale would alter the behavior of gravity at short distances. Newton's inverse-square law ($1/r^2$) holds strictly in three spatial dimensions; at distances smaller than the compactification radius of an extra dimension, the gravitational force law changes. Precision tabletop torsion-balance and micro-cantilever experiments have tested Newton's law down to approximately 30 micrometers without finding any deviation. The dark dimension proposal places the expected breakdown of the inverse-square law at roughly 10 micrometers—just beyond the reach of existing tabletop tests, but within striking distance of near-future apparatuses. Meanwhile, an astrophysicist analyzed data from the Planck satellite and ground-based telescopes to see if cosmological signatures could already test the concept. The current observational answer is negative, though she noted that upcoming surveys could eventually "confirm or rule out string theory models of the dark sector."

```mermaid flowchart TD accTitle: Dark Dimension Mechanism and Testing accDescr: Diagram illustrating how the dark dimension leads to massive gravitons and sub-millimeter gravity deviations.

subgraph Theory["Theoretical Setup"] SM["Standard Model Matter<br/>(Confined to 3D Brane)"] ED["Dark Dimension<br/>(One extra dimension ~10 μm)"] Grav["Gravitons<br/>(Leak into extra dimension)"] end

subgraph Effects["Physical Consequences"] KK["Massive Gravitons<br/>(Act as Dark Matter)"] Dev["Deviation from 1/r²<br/>(At distances < 10 μm)"] end

subgraph Tests["Experimental Status"] Lab["Tabletop Experiments<br/>(Tested to 30 μm: Null)"] Cosmo["Cosmic Surveys / Planck<br/>(Current data: Inconclusive)"] end

SM -.-> Grav ED --> Grav Grav --> KK ED --> Dev Dev --> Lab KK --> Cosmo ```

- **Braneworld Confinement:** Quarks and electrons sit on a three-dimensional spatial membrane, while gravitons penetrate the full higher-dimensional bulk. - **Massive Gravitons as Dark Matter:** Gravitons propagating in the dark dimension manifest as massive states whose properties are tuned to match dark matter observations. - **Sub-Millimeter Deviations:** Newton's law has been verified down to roughly 30 micrometers; the new model predicts deviations from $1/r^2$ will appear around 10 micrometers.

---

[04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) Institutionalized Pseudoscience and the Moving Goalposts

Sabine Hossenfelder cuts through the excitement with a harsh assessment rooted in the arguments of her book, *Lost in Math*. She points out that the foundations of physics are caught in an endless, predictable loop: researchers propose a model that is framed as "intriguingly testable" by an experiment slated for the near future; the experiment runs and finds nothing; theorists discard the specific parameter values; and they immediately invent a new twist to pitch to mainstream outlets like *The Economist*. Hossenfelder rates the claim "a solid 10 out of 10 on the [bullshit] meter." She notes that discovering an extra spatial dimension would merely be empirical evidence for an extra dimension, not evidence for string theory itself, especially since the mechanism is not derived from string theory principles but merely "conjectured into place."

The real scandal, in her view, is that academics at prestigious institutions continue to draw salaries for promoting what she characterizes as "institutionalized pseudoscience," while science journalism uncritically amplifies their moving targets. If tabletop gravity experiments push past 10 micrometers and discover nothing, Hossenfelder sarcastically predicts that string theorists will announce that the theory remains conveniently testable at an even smaller, "more exciting distance."

Turning from academic dysfunction to foundational learning, Hossenfelder reflects on her two school-aged children and her desire for better science and mathematics education. She introduces the video's sponsor, Brilliant, an online platform teaching math, science, and coding through problem sets and a newly launched AI tutor. The tutor guides students through problems step by step by prompting their existing knowledge rather than handing out answers, allowing learners to freely pursue topics that spark their curiosity. Viewers are invited to try the tutor for free and receive 20% off an annual subscription via `brilliant.org/Sabine`.

- **Moving the Goalposts:** Whenever an experiment fails to find evidence at a predicted scale, theorists adjust the parameters and declare the idea testable at the next technological frontier. - **Conjectured vs. Derived:** Extra dimensions are not exclusive to or derived from string theory; finding one would not prove strings or quantum gravity. - **Educational Sponsor:** Brilliant's interactive platform and step-by-step AI tutor offer math, science, and coding instruction, with a 20% discount on annual subscriptions for viewers.

## Notable quotes > [00:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=0s) String theory has been famously untestable for decades. — Sabine Hossenfelder

> [00:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=0s) This week the Economist reported that has changed, and the reason involves an extra dimension of space that might be just big enough to notice in a tabletop experiment. — Sabine Hossenfelder

> [00:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=0s) not a joke about the present state of academia — Sabine Hossenfelder

> [02:04](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=124s) confirm or rule out string theory models of the dark sector.

> [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) intriguingly testable — Sabine Hossenfelder

> [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) a solid 10 out of 10 on the [bullshit] meter. — Sabine Hossenfelder

> [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) conjectured into place. — Sabine Hossenfelder

> [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) institutionalized pseudoscience — Sabine Hossenfelder

> [04:00](https://www.youtube.com/watch?v=8_DFiI2wr1U&t=240s) more exciting distance. — Sabine Hossenfelder

## Mentioned Sabine Hossenfelder, The Economist, Standard Model, Cumrun Vafa, Harvard, Planck satellite, Lost in Math, Brilliant

## Video description Click the link below or scan the QR code to get started with Brilliant’s tutor for free. You can upgrade to Premium to unlock all courses. And right now, Science with Sabine viewers can save 20% off an annual subscription at https://Brilliant.org/Sabine/

String theory has been famously untestable for decades. This week the Economist reported that has changed, and the reason involves an extra dimension of space that might be just big enough to notice in a tabletop experiment. There is a rather different way to read the situation. Let's take a look.

Paper: https://doi.org/10.48550/arXiv.1806.08362

#stringtheory #physics #darkmatter #sciencenews #science

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[Source](https://www.youtube.com/watch?v=8_DFiI2wr1U)

中文简报

霍森菲尔德驳斥哈佛弦理论“暗维度”主张 称微米级额外维度让弦理论具备可检验性的说法不过是转移理论目标，等同于制度化的伪科学。 由 Cumrun Vafa 领导的哈佛研究小组近期提出，弦理论可以通过一个“暗维度”同时解释暗能量与暗物质——即一个在微米尺度而非微小普朗克尺度上紧致化的额外空间维度。在该模型中，泄漏至额外维度的引力子表现为具有质量的暗物质粒子，并导致牛顿平方反比引力定律在约10微米处失效，这一尺度恰好略超出当前桌面实验所测试的30微米阈值。Sabine Hossenfelder 抨击这种热潮是“制度化的伪科学”，指出这些参数纯属推测而非推导得出，且发现额外维度也仅能证明额外维度本身的存在，并不能证明弦理论。她最终将该提议定性为一个典型范例，表明理论物理学家如何为了迎合媒体炒作，而不断将理论预言推到实验刚好无法企及的范围之外。 由 Cumrun Vafa 领导的哈佛理论物理学家在弦理论中提出了一个“暗维度”，认为存在一个在大致微米尺度上紧致化的单一额外空间维度，用以统合暗物质与动态暗能量。 (0:00) 该模型假设泄漏至额外维度的引力子会获得有效质量并表现为暗物质，预言在约10微米处会出现偏离牛顿平方反比定律的现象——刚好超出当前30微米的实验探测极限。 (2:04) Sabine Hossenfelder 批评该提议是在转移目标并属于“制度化的伪科学”，认为发现额外维度并不能证明弦理论，且若近期实验未获得任何结果，理论学家只会进一步缩小设定的尺度。 (4:00)

Reading summary

Proponents of string theory claim the framework yields a testable prediction through a micrometer-scale "dark dimension" resolving dark matter and dark energy, but Sabine Hossenfelder argues the model merely shifts theoretical goalposts just beyond current experimental reach. The String Theory Landscape and Dynamic Dark Energy (0:00) String theory has struggled for decades with untestability and the mathematical challenge of the string theory landscape, an estimated 10^500 possible vacuum configurations from which physicists have yet to isolate the Standard Model. Seeking a way forward, theoretical physicists argued in 2018 that string theory requires dark energy to vary over time rather than remain a constant, a conjecture that received tentative support from recent cosmological surveys. Capitalizing on these observational hints, a Harvard research team led by Cumrun Vafa proposed modifying the geometry of the extra spatial dimensions required by the theory. Instead of curling all six extra dimensions down to the inaccessible Planck scale, the group posited that five dimensions remain microscopic while a single "dark dimension" is rolled up at a comparatively macroscopic scale of approximately one micrometer. Massive Gravitons and Sub-Millimeter Gravity Tests (2:04) The proposal operates within a braneworld scenario where Standard Model particles are confined to a three-dimensional spatial membrane, but gravitational quanta—gravitons—are free to propagate through the higher-dimensional bulk. As gravitons enter the dark dimension, they acquire an effective mass from our perspective; Vafa's team suggests these massive gravitons could constitute cosmic dark matter, calibrated to match astronomical observations. Because an extra dimension modifies the gravitational force law at scales smaller than its compactification radius, the hypothesis anticipates a breakdown of Newton's inverse-square law. Existing tabletop torsion-balance and micro-cantilever experiments have confirmed Newton's law down to roughly 30 micrometers without detecting deviations. The dark dimension hypothesis sets the breakdown threshold at approximately 10 micrometers, placing it just out of range of current tests but accessible to near-future apparatuses. Meanwhile, analyses of Planck satellite and ground-based cosmological data remain inconclusive regarding dark sector signatures. Methodological Skepticism and Moving Experimental Goalposts (4:00) Hossenfelder rejects the characterization of the dark dimension as a genuine test of string theory, arguing it perpetuates an ongoing cycle in the foundations of physics. In this recurring pattern, theorists construct models whose parameters are placed just beyond the threshold of current technological capability, only to adjust the numbers and pitch a revised scenario to media outlets when experiments yield null results. Furthermore, Hossenfelder emphasizes that detecting an extra spatial dimension would validate only the existence of higher dimensions, not string theory itself. Because the dark dimension mechanism is conjectured into place rather than rigorously derived from fundamental string principles, she characterizes the practice as institutionalized pseudoscience that avoids falsification by continually moving its predictions to smaller distances. While forthcoming tabletop gravity experiments and astronomical surveys may soon probe the 10-micrometer threshold, the dark dimension debate exposes deep divisions over whether tweaking parameter scales represents legitimate empirical forecasting or an unfalsifiable defense of string theory.

Source quotes

[0:00] Sabine Hossenfelder: String theory has been famously untestable for decades. [0:00] Sabine Hossenfelder: This week the Economist reported that has changed, and the reason involves an extra dimension of space that might be just big enough to notice in a tabletop experiment. [0:00] Sabine Hossenfelder: not a joke about the present state of academia [2:04] confirm or rule out string theory models of the dark sector. [4:00] Sabine Hossenfelder: intriguingly testable [4:00] Sabine Hossenfelder: a solid 10 out of 10 on the [bullshit] meter. [4:00] Sabine Hossenfelder: conjectured into place. [4:00] Sabine Hossenfelder: institutionalized pseudoscience [4:00] Sabine Hossenfelder: more exciting distance.

Original transcript

[0:00] String theory has finally made a testable  prediction. I read this in The Economist this [0:07] week. New theories and experiments should shine  light on string theory. And proponents claim that [0:14] string theories made a testable prediction. And  not just this, it's something to do with dark [0:20] dimensions, which I swear is not a joke about  the present state of academia. It's instead [0:26] an attempt to use string theory to explain dark  matter and dark energy. And that would of course [0:33] be very very interesting. So let's have a look.  String theory was supposed to be the theory of [0:38] everything that explain why the particles of  the standard model are what they are and how [0:43] they interact with gravity. Unfortunately turned  out that there's not just one string theory but an [0:49] enormous number of them. An estimated 10^500 or  so. This is called the string theory landscape. [0:56] And in this landscape, no one's yet found even one  string theory that's compatible with the standard [1:03] model of particle physics. Nevertheless,  string theorists are convinced they're on [1:08] the right track. And in the past decade, they've  tried to make their case in a new way. In 2018, [1:15] some string theorists argue that in string theory,  dark energy could not be constant, but it would [1:21] have to depend on time. And would you know it,  in the past 2 years, we've indeed seen evidence [1:28] that dark energy does depend on time. This is very  intriguing indeed, isn't it? Naturally, the group [1:34] at Harvard around Cumrun Vafa which put forward  the idea tried to get more out of this. For this, [1:41] they looked at the additional dimensions of  space that string theory requires. In total, [1:46] there are six additional dimensions. Usually,  string theorists assume that they're way too small [1:51] to be measurable. They're rolled up to extremely  tiny radius and we just can't measure such a tiny [1:58] radius. This is why string theory is so difficult  to test. But this group says look if one of those [2:04] dimensions is small but not super small somewhere  on the scale of a micrometer then that could also [2:12] explain dark matter. This is because if there is  such an extra dimension then gravity knows of it. [2:19] The particles of the standard model electrons  and quarks and so on they sit on a slice with [2:24] three dimensions of space. This is our universe.  But gravity goes into all dimensions. And since [2:30] this is a theory of quantum gravity, gravity  has quanta. These are the gravitons. And the [2:36] gravitons that go into the extra dimensions, they  become massive. And that the string theorists say [2:42] is what dark matter is made of. These massive  gravitons in the extra dimensions. Concretely, [2:48] they say that if one of the extra dimensions  has a radius in the range of some micrometers, [2:53] then this fit to the observations of dark matter.  This is why they called it a dark dimension. And [3:00] yes, that can be tested directly. This is because  Newton's law depends on the number of dimensions. [3:06] The 1/rˆ2 are actually only true in three  dimensions of space. If you could measure Newton's [3:12] law in distances so small that they're below the  radius of the extra dimension, then you could see [3:18] deviations from Newton's law. This has been tested  down to about 30 micrometers and no deviations [3:25] from Newton's law have been seen. The dark  dimensions proposal puts the deviation at about [3:30] 10 micrometers. That's why they say string theory  is now testable. New is just recently that just [3:36] in July an astrophysicist turned to cosmological  data to see whether the dark dimension idea could [3:43] be tested with data from the plank satellite and  some earthbased telescopes. The answer is no at [3:51] present. But she writes that future surveys could  quote confirm or rule out string theory models of [3:57] the dark sector. What are we to make of this?  Well, if you read my book, "Lost in Math", that [4:05] should sound very familiar. In the foundations of  physics, ideas are always intriguingly testable [4:12] with an experiment that'll be done in the near  future. Then the experiment is done and it doesn't [4:18] find any evidence of whatever they predicted.  Then they throw out the idea and try to fool [4:24] you with the next one and you'll read about it  in the economist. It's a solid 10 out of 10 on [4:30] the [ __ ] meter. If we had evidence for an extra  dimension of space and well that would be evidence [4:37] for an extra dimension of space. You don't also  need strings for this. And the idea isn't derived [4:44] from string theory either. It's just conjectured  into place. So why am I telling you about this? [4:50] It's to remind you that there are people who call  themselves scientists at top universities who get [4:57] paid for this nonsense and that this continues to  go on and that it gets reported in the media. I [5:04] don't talk about it a lot because it's terribly  boring, but it's institutionalized pseudocience [5:12] and that's the real story that the economist  should be writing about. If future experiments [5:17] find nothing at 10 micrometers, I confidently  predict that string theory will remain testable [5:23] at an even more exciting distance. I have two  children in school and I have opinions about [5:30] their maths and science education. In my opinion,  it could be better. Luckily, today's sponsor, [5:36] Brilliant, helps my kids to get ready for  the future, and they can help yours, too. [5:42] Brilliant is an online learning platform with a  large number of courses on mathematics, science, [5:47] and coding. They just recently introduced a new  AI tutor that'll walk children through the problem [5:54] sets, not by giving away the answers, but by  helping them when they're stuck, reminding them of [6:00] what they already know, and explaining each step.  I really think this is the future of education. My [6:06] children especially like it that Brilliant doesn't  tie them to a specific topic, but that they're [6:12] free to explore whatever piques their curiosity.  And of course, I have a special offer. You can get [6:18] started with Brilliant Tutor for free. And if you  use my link, brilliant.org/Sabine or scan the QR [6:26] code, you can save 20% on an annual subscription.  Thanks for watching. See you tomorrow.