Community Events

Colorectal cancer (CRC) kills around 700,000 people worldwide every year. The majority of these deaths are the result of the dissemination of the disease to foreign organs. The emergence of new treatment options for patients with late-stage CRC has extended survival periods, yet metastases remain incurable for the majority of patients. The mechanistic basis of metastasis in CRC is not well understood. There are no prevalent mutations associated with metastatic dissemination. New evidence from our laboratories and other groups now points to a key role for the interaction between the tumor and the surrounding cell ecosystem that includes immune cells, fibroblasts and blood vessels. For instance, the global gene expression program that associates more robustly to metastasis in CRC patients was expressed by cells that surround the tumor, the so-called cancer-associated fibroblasts (CAFs), and not by the cancer cells themselves. Besides these transcriptional mechanisms, the physical properties of cancer cells and cells of the tumor ecosystem and their mutual interaction are increasingly regarded as essential ingredients for CRC progression.

In this ICREA colloquium the speakers presented the recent advances from their groups addressing the mechanisms that govern progression of CRC, highlighting the need to integrate tools and concepts from genetics to physics. We emphasized the key role of the tumor ecosystem interactions and discuss how it can be studied through multidisciplinary strategies.

Our understanding of the Universe at the most fundamental level is based on two seemingly radically different theories. Einstein’s General Relativity describes the gravitational force that governs physical processes on the largest possible scales. The revolutionary experimental discovery of gravitational waves, little ripples on the geometry of spaces and time, is the latest confirmation of Einstein’s theory. The other three forces in Nature, the electromagnetic, the strong and the weak force, are unified in a single framework known as Quantum Field Theory, which describes subatomic processes. The most important discovery in theoretical physics in the last 25 years is an exact equivalence between Quantum Field Theory in 1 time and 3 spatial dimensions, as in our Universe, and General Relativity… in one dimension higher! I will describe the basis of this correspondence, known as Holography, as well as applications to particle physics, cosmology and gravitational waves.

As AI systems start being deployed in a large number of everyday contexts, it is particularly important to study the transparency and trustfulness of these systems from different perspectives.

In the first part of the joint talk, the speakers considered whether AI systems can have disadvantageous consequences for people based on the social group to which they belong, i.e., whether AI can engage in indirect discrimination, specifically statistical group discrimination.  Various examples of this phenomenon were shown, which seems quite pervasive and particularly affects high-risk applications of AI, such as those related to housing, employment, and the administration of justice.
In the second part, the speakers considered to what extent large AI systems trained to “speak English” by being exposed to large amounts of text are really understanding natural language like humans do, and to what extent they have instead developed an alternative communication code that is only superficially resembling English. Surprising results that suggest that the second hypothesis is correct, and the implications that this might have in terms of the usability and safety of these systems were shown.

In these two talks argued that linguistic diversity is not some sort of irrelevant “noise” grafted on a universal abstract structure, but that, instead, diversity is highly patterned and scientifically relevant. “True” universals are rare and, just like in biology, they emerge from diversity through evolution, in this case, cultural evolution. One such possible universal concerns the finding that the rate at which information is transmitted tends to be the same across very different languages, resulting from a fundamental trade-off between speech rate (how fast a language is spoken by its speakers) and information density (determined by the language’s structure). This trade-off shows, in our view, that the speakers and the language are two inseparable sides of the same coin, and that constrains resulting from our speech organs, hearing and cognition act on language, forcing it to adapt to fit an optimal region of the communicative niche. Switching to differences between languages, we will marshal a number of examples of languages that do or do not have a certain feature (a specific word for blue, or sounds such as “f” and “v”) because of the environment they are spoken in (how much ultraviolet light there is?) or by whom they are spoken (what kind of food do their speakers eat?). We will argue that such patterns of diversity, just like in biology, reflect adaptation to different constraints and affordances, only that in this case we are speaking of cultural entities evolving culturally.

While such ideas are far from being new, the recent explosion in the availability of cross-linguistic data, of extremely powerful statistical methods and affordable computing power, and the increased cross-disciplinary collaborations have all conspired in making possible a “silent paradigm shift” in the language sciences.

The 2015 direct detection of gravitational waves (GW) opened a new era in our ability to explore the Universe. Since then, the scrutiny of the 10 – 1000 Hz band by the LVK collaboration has detected more than a hundred of mergers of black holes with masses in the range between few times and hundred times the mass of the Sun. In 2023 a signal in the nHz was detected by other methods, and its origin is currently being discussed.

In this colloquium, the speakers addressed the significance of this detection, the possibilities and status of exploration in different bands of the spectrum of GWs, and discussed one of the most promising ways forward: the Einstein Telescope, with strong leadership from Barcelona institutions.