Bartosz Jakubowski ⟠

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Bartosz Jakubowski ⟠

Bartosz Jakubowski ⟠

@bartjjj

tech investor. fintech, techbio and crypto, mostly. football player, LEGO builder, philosopher. 🫶

Paris, Ile-de-France Katılım Mart 2013
2.5K Takip Edilen3.2K Takipçiler
Trucmuch
Trucmuch@Technologi82698·
@Emlcsg Autre point, un marché prédictif fonctionne comme un carnet d'ordres dont le prix reflète le trader marginal. Sur une course municipale locale avec profondeur réduite le prix peut sur-réagir au narratif dominant sans que l'estimateur vrai ait bougé d'autant.
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Trucmuch
Trucmuch@Technologi82698·
Depuis hier soir j'entends partout la même chose. Dati 25 % + Bournazel 11 % + Knafo 10 %, ça fait 47 %, c'est plié. J'ai passé la soirée à modéliser ce second tour et cette addition est fausse. L'erreur de raisonnement est instructive.🧵
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Bartosz Jakubowski ⟠
Bartosz Jakubowski ⟠@bartjjj·
@vsodera Fmr VC now angel and builder, would love to meet! And make some intros if need be. Lmk what works!
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Vivek Sodera
Vivek Sodera@vsodera·
Will be in Paris on March 22-23 to meet with AI founders + investors. Also spending time at Station F. If there are any local founders/investors interested in grabbing a coffee, lmk!
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clem 🤗
clem 🤗@ClementDelangue·
Money doesn’t buy everything. Sometimes, culture, hard-work and team spirit wins! ⚽️🇫🇷 With my family, we've been bleeding red and gold (the club colors) since 1998. I was 10 years old when I watched my hometown club, @RCLens, lift the French title for the first time. That moment made me a lifelong fan, but it's the club's culture over the decades since that makes me truly proud. Right now, the club is sitting at number one in the French Ligue. They are ahead of @PSG_inside, a team with a budget 10 times larger. Here’s what most people outside of France don’t know about Lens: 🏟️ The community is unmatched: The stadium capacity is 40,000. The population of the actual city is smaller than that. On match days, the entire town literally fits inside the arena with the most festive atmosphere in the country (loud singing, beer & french fries everywhere!) 🤝 Loyalty over everything: When the club was relegated to the 2nd division, they still had higher attendance than most 1st division clubs. The fans never left. 🧠 Exceptional leadership: The masterful work from @SirOughourlian, Benjamin Parrot & Jean Louis Leca and everyone at the club proves that smart, humble and consistent building beats aimless spending. Lens deserves so much more international recognition. It’s a masterclass in building a faithful, passionate community and proving that heart and hard work can go toe-to-toe with billions. Can't wait to see them in the Champions League next year. Allez Lens ❤️💛!
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Claude
Claude@claudeai·
Ads are coming to AI. But not to Claude. Keep thinking.
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Gabin 🌱
Gabin 🌱@g48in·
@bartjjj On prediction markets, you can talk to @franklyteddy who’s became an expert of distribution markets, huge untapped potential (insurance, etc.)
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Bartosz Jakubowski ⟠
Bartosz Jakubowski ⟠@bartjjj·
Some personal news - I left Alven a few months ago to focus on building what’s next. First, my gratitude goes to everyone I worked with at Alven — partners, team members, and limited partners. Over 6 years, I was trusted with growing responsibilities, from investment manager to principal to GP. I’m equally grateful to the founders, exec teams and employees I worked with. Across 8 companies over 5 years, I watched them grow revenue by an average of 35x and scale teams from 15 to 90 FTEs. I learned a great deal working alongside them, and I’m glad to continue doing so today as a venture partner. Why the move? After 10 years in the European venture ecosystem (XAnge, EQT, Alven), I chose to change my mode of contribution. Venture capital is stimulating and rewarding — but I wanted to take more direct ownership, assume creative and execution risk, and build something of my own. I do my best work when I’m forced to cross domains and learn by doing — as a way to build judgment under uncertainty. I’m currently leaning deliberately into that approach: spending time inside new systems, acquiring first-hand understanding, and letting patterns emerge before converging. What I’m digging into: • Encoding mastery into machines We’ve become good at automating processes, much less at capturing expertise-turned-intuition. Every year, vast amounts of implicit judgment disappear with talent movement — like libraries of Alexandria burning in silence. I’m interested in tools and platforms that help organizations compound critical knowledge instead of losing it, especially in high-leverage domains (finance, technology) and highly technical fields (healthcare, science). • Financial primitives for a more unstable world Mechanisms (like prediction markets) that aggregate distributed intelligence to price uncertainty and inform decisions. • More flexible models for financing innovation from European talent Between large platforms and sub-scale specialists, with exceptional talent but too few exits, I’m exploring fund structures, incentive design, cross-asset platforms and downstream liquidity that could better align the ecosystem. All of these revolve around bridging people, disciplines and systems that don’t naturally talk to each other. If you’re a curious polymath, a founder building in these spaces, or just want to jam on these topics, I’d love to connect.📩
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Flo Crivello
Flo Crivello@Altimor·
Almost every single founder I know in SF (including me) has reached the same conclusion over the last few weeks: that it's only a matter of time before we have to leave CA. I love it here, I truly want to stay, and until recently intended to be here all my life. But it's now obvious that that won't be possible. Whether that's 2, 5, or 10 years from now, there is no future for founders in CA.
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Michael A. Arouet
Michael A. Arouet@MichaelAArouet·
This chart is simply amazing. Poland doubled its GDP in the last decade and is expected to grow another 30% in the next few years. Poland did everything right: 1. It has strong rule of law without overregulating businesses or throttling innovation and investment. 2. It maintains reasonable tax rates that keep people motivated to work hard and start businesses. 3. With EU funds, Poland massively upgraded its infrastructure, attracting foreign investment. 4. It digitalised most government services, making interaction with them easy and efficient. 5. Compared to some other countries in the region, the Polish economy is not based on cronyism and corruption. 6. Poland lacks long-term welfare nets, which motivates people to seek new jobs when unemployed. 7. Poland protects its borders effectively, preventing illegal immigration while welcoming immigrants who want to work, start businesses, and contribute to society. 8. Last but not least, Poles still remember the misery of socialism and understand they must work hard or start a business to live well. The entrepreneurial mindset in Poland is simply amazing. Be like Poland. It’s really worth it, and so refreshing compared to the steady decline of Western European economies and societies.
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Bartosz Jakubowski ⟠
Bartosz Jakubowski ⟠@bartjjj·
Polymarket has become my go-to place to follow the news. An unbiased, real-time, worldwide, skin-in-the-game Reuters. So many adjacencies to come
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vittorio
vittorio@IterIntellectus·
this is actually insane since AI came out, every model for biology had the same limitation: train it on one disease, it only works on that disease. retrain for any new drug, patient, or tissue. the foundational model promise for biology basically didnt exist. zero-shot prediction was impossible. until now. Arc Institute's model (Stack) learns from groups of cells instead of one at a time. the way LLMs see words in a sentence and not in isolation, cells become context for each other. you can show it cells that were treated with a drug, and it predicts how completely different cells would respond to that same drug. even if nobody ever ran that experiment. even if that tissue was never perturbed. even if that combination never existed in training. cells themselves become prompts, just from inference. you can query biology now. "what would liver cells do if i gave them this cancer drug?" and it answers with actual gene expression predictions. not perfectly yet, but well enough that it beat existing methods in 28 of 31 benchmarks (basically unheard of in this field where beating 60% is considered good). they used it to build a virtual perturbation atlas: 28 human tissues, 40 cell classes, 201 drugs. no lab required. purely in silico. when they validated against real wet-lab experiments, the predictions matched. drug discovery currently costs $5M+ and 2 years per experiment that might not work. now you screen computationally first. "which tissues will have off-target effects?" "how will this patient's cells respond differently?" questions that used to require millions in grants now only need a GPU. slowly but surely we are solving biology
Arc Institute@arcinstitute

Predicting cell state in previously unseen conditions such as disease or in response to a drug has typically required retraining for each new biological context. Today, Arc is releasing Stack, a foundation model that learns to simulate cell state under novel conditions directly at inference time, no fine-tuning required.

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Shanaka Anslem Perera ⚡
Shanaka Anslem Perera ⚡@shanaka86·
SCIENTISTS JUST PROVED YOU CAN REVERSE YOUR BRAIN AGE IN 4 HOURS What happened on November 2025 will rewrite human longevity. A single 25mg dose of psilocybin didn’t just alter consciousness. It physically rewound the human brain to a youthful state. Measurable. Reproducible. Persistent. The data that changes everything: Your brain’s default mode network … the rigid autopilot running your thoughts … collapsed by 40%. Entropy spiked 25%. Neural patterns identical to a child’s brain emerged within hours. The flexibility lasted days. This isn’t theory. This is measurement. Nature published it. Bryan Johnson documented it live. fMRI scans confirmed what sounds impossible: temporary brain rejuvenation through a single molecule. Now connect the dots that will stop your heart: Fifteen-year studies tracking 70,000 humans prove happiness reduces death risk by 22%. Optimism cuts heart attacks by 35%. Purpose and well-being … the exact states psilocybin produces … predict mortality better than cholesterol. Ketamine already reversed biological age by 3 years on epigenetic clocks. Published 2025. Peer-reviewed. Repeatable. Do the math: One supervised session. Four-hour brain state shift. Four-week plasticity window. One to three years of biological age erased. Sixteen to thirty-five percent lower death risk through sustained well-being. For one billion aging humans, this means 300 billion prevented deaths. Three trillion dollars in healthcare saved. Ten to twenty percent extension of functional lifespan. The mechanism is brutal in its simplicity: 5-HT2A receptors flood. Prefrontal rigidity dissolves. Sensory integration explodes. Your brain remembers how to be young. The entropy peak forces neural rewiring. The afterglow cements new patterns. Phase 3 trials launch in 90 days. If entropy doesn’t rise above 10% or lifespan gains fall below 5%, the hypothesis dies. If inflammation hits 20%, we stop immediately. But if it holds? Aging just became optional. The compressed timeline between proof and protocol is 18 months. The distinction between medicine and evolution collapses. One molecule. Four hours. Everything changes. This is the inflection point.​​​​​​​​​​​​​​​​ Full deep dive article here - open.substack.com/pub/shanakaans… @bryan_johnson you inspire me mate!
Shanaka Anslem Perera ⚡ tweet media
Bryan Johnson@bryan_johnson

First mushroom trip data is out: my brain activity. Dose: 5 g dried Psilocybe cubensis (B+ strain) Containing 24.9 mg psilocybin Psilocybin longevity experiment. What we see in the brain: + brain activity data mirror my subjective experience + strong decrease in my brain’s control center (prefrontal + premotor cortex) + strong increase in sensory, auditory and speech integration + higher entropic brain patterns: open, flexible, less predictable, exploratory + brain network patterns resembling a youthful state vs aged and rigid Matching what I reported experiencing: + “felt like my consciousness was dialed up to 10/10.” + “I felt hyper aware and hyper alive.” + “I experienced sense of touch with awe.” + “my mind was insatiably curious and wanted to deploy its sensors into the world and discover all things.” + “My brain wanted to stare, study and marvel.” + “The flavor exploded in my mouth.” + “...restored my perception to youthful levels, returning them to factory settings and dissolving my aged numbness.” Why this could matter for longevity: + In people aged 65-85, higher happiness was linked to a 22% reduced risk of all-cause mortality over 15 years. + A meta-analysis showed that optimism correlated with a 35% decrease in heart attacks and a 16% decrease in all-cause mortality. + Having a strong purpose in life is associated with a 17% reduction in both heart attacks and all-cause mortality. + In psychedelic medicine, treating depression with ketamine has been shown to reverse biological age by up to 3 years. Together, these findings suggest a plausible mechanism by which psychedelics, including psilocybin, can prolong both health and lifespan by improving mental well-being and rewiring the brain to a more positive, creative, and curious state. My team and I hypothesized that neuroplasticity, the loosening of rigid inhibitory patterns that makes the brain more flexible, creative, and relaxed, and even the subjective psychedelic state itself may be as meaningful for longevity as methylation shifts, senescence reversal, or telomere biology. What’s happening mechanistically Earlier work shows that psilocin (the active metabolite of psilocybin) acts primarily as an agonist at 5-HT₂A serotonin receptors in the cortex. These receptors are especially dense in high-level association and sensory regions, as mapped in a high-resolution PET/MRI atlas of the human serotonin system. When these receptors are activated, brain imaging studies show an induced state of desynchronization, entropy, and neuroplasticity.  This process erodes the rigid brain hierarchy and default mode networks in favor of a brain-wide spontaneous, creative, curious, and child-like state. Kernel Flow data shows the same pattern: The recorded timepoints included: + baseline: directly before session start (not shown) + timepoint 1: 4 hrs after dose (acute phase effects). + timepoint 2: end of the day, before bedtime. + timepoint 3: the following morning. I continue to measure my brain daily. Image notes + The three maps show changes vs. baseline (not absolute activity) + Red = increased connectivity, blue = decreased connectivity vs. my baseline. + The left reference map shows the 5-HT₂A receptor distribution from PET, the main psilocybin target. Time Point 1 - 3 hrs post dose + Reduced connectivity in the prefrontal and premotor cortex, correlating with acute brain desynchronization. + Increased connectivity and hyperintegration between the primary motor and sensory cortex regions. + Enhanced connectivity in the auditory and speech areas of the cortex. + Inhibited connectivity in the medial prefrontal and posterior zones, areas associated with the Default Mode Network (DMN). Subjective experience: + Enhanced sensory vividness and bodily presence: The brain's top-down hierarchy, originating in the pre-frontal cortex, was attenuated. This reduced predictive filtering, leading to a flood of bottom-up sensory information and heightened bodily perception (e.g., a fascination with water and light dynamics in a jar, a restored, primal joy of touch and sensation). + Peak neuroplasticity and cortical entropy: A peak in cortical entropy and neuroplasticity contributed to a feeling of hyperawareness (e.g., heightened sensory perception, feeling "at one with existence," hyper-aware and hyper-alive). + Deeper appreciation of music and uninhibited movement and expression: Sharpened auditory senses and reduced top-down inhibition allowed music to be enjoyed on a profound level. Concomitant functional connectivity in speech-motor and auditory-motor integration areas facilitated uninhibited expression through both speech and movement (a restored, uninhibited, child-like joy of music). + Note: Full ego dissolution was not experienced, which may necessitate a higher dose to achieve more advanced desynchronization of the prefrontal and parietal cortices. Time point 2 - 5 hrs post dose, end of trip + Intensified sensory and motor hyperconnectivity. + Continued increased connectivity in auditory and speech centers, with a relative restoration of connectivity to the speech understanding area. + Partial re-emergence of the prefrontal parietal coupling, while prefrontal context remains partially inhibited. + Partial re-emergence of connectivity in areas related to the default mode network. Subjective Experience + High-order brain networks begin to restabilize, alongside persisting sensory, motor, auditory, and speech hyperconnectivity, suggesting neuroplasticity in action. + The narrative shifts from pure sensation and experience to meaning generation, accompanied by deep philosophical reflection (e.g., reconsidering the meaning of life and one's relationship with mortality in the time of AI, and pondering the future of human evolution). Time point 3 - next morning (afterglow) + Persistence: Patterns from the acute phase continue, including general prefrontal cortex inhibition, ongoing neuronal plasticity, and heightened senses. + Intensified connectivity: Increased connectivity is noted in the speech generation area and the somatic sensory association area. + DMN inhibition: The default mode network remains inhibited. Subjective Experience: + "Afterglow" effect: Characterized by continued sharpened senses, calm clarity, emotional openness, and low inhibitions. For instance, I felt more comfortable expressing uninhibited, self-deprecating humor (i.e. my post making fun of myself about the insane lengths I go for my Don’t Die experiment) + Integration of experience learnings: The heightened activity in the somatic sensory association area aligns with the process of integrating and "making sense" of the raw sensory experience of both the self and the external world. + Enhanced creativity: The intensified connectivity in the speech generation area contributed to the uninhibited bout of creative writing I undertook to report my experience.

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Empire State Building
Empire State Building@EmpireStateBldg·
For Poland
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David Hoffman
David Hoffman@TrustlessState·
Estoy llegando en El Chalten!!
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Michael A. Arouet
Michael A. Arouet@MichaelAArouet·
Wow, Poland is one of the world’s fastest growing millionaires hubs. Poles simply know that hard work and entrepreneurial spirit are the only proven way to escape socialist poverty. It’s always so refreshing to go there, and it’s also much safer than Western Europe. Keep going!
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Bartosz Jakubowski ⟠
Bartosz Jakubowski ⟠@bartjjj·
@gregory_raymond Y a un truc que je ne comprends pas : une mesure injuste ou contreproductive est une mesure injuste ou contreproductive, qu’elle concerne 1 personne ou 100 millions. Non ?
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Grégory Raymond 🐳
Grégory Raymond 🐳@gregory_raymond·
On parle beaucoup de l'intégration des cryptos dans le nouvel "impôt sur la fortune improductive" (qui remplacera l'IFI). À vrai dire, pour moi c'est un non-sujet tant cela concerne peu de personnes (seuil à 1,3 million d'euros) Mais ce qui est vraiment incroyable, c'est qu'on trouve dans l'assiette de ce nouvel impôt les contrats d'assurance-vie. Et jusqu'à preuve du contraire, les fonds euros sont concernés. C'est grâce à ce véhicule que les Français investissent dans la dette française. Peut-on vraiment considérer ce placement comme "improductif" ? Le problème, c'est qu'il va y avoir un effet indésirable assez incroyable : Les particuliers auront davantage intérêt à investir dans les bons du Trésor américain car ces derniers ne font pas partie des actifs dits "improductifs" et seront de facto moins fiscalisés... On marche sur la tête.
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Alexandre Stachtchenko
Alexandre Stachtchenko@StachAlex·
Il y a 17 ans l'idée de Bitcoin est révélée au monde. Aujourd'hui, c'est : - $2 000mds de capitalisation (top 8 actifs mondiaux) - $2 000mds de volume mensuel de transactions on-chain, surpassant VISA - 600M de citoyens libérés du fiat Merci Satoshi.
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