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Understanding the Universe with DESI

DESI helps unveil the mysteries of dark energy and cosmic structures.

DESI Collaboration, A. G. Adame, J. Aguilar, S. Ahlen, S. Alam, D. M. Alexander, C. Allende Prieto, M. Alvarez, O. Alves, A. Anand, U. Andrade, E. Armengaud, S. Avila, A. Aviles, H. Awan, B. Bahr-Kalus, S. Bailey, C. Baltay, A. Bault, J. Behera, S. BenZvi, F. Beutler, D. Bianchi, C. Blake, R. Blum, M. Bonici, S. Brieden, A. Brodzeller, D. Brooks, E. Buckley-Geer, E. Burtin, R. Calderon, R. Canning, A. Carnero Rosell, R. Cereskaite, J. L. Cervantes-Cota, S. Chabanier, E. Chaussidon, J. Chaves-Montero, D. Chebat, S. Chen, X. Chen, T. Claybaugh, S. Cole, A. Cuceu, T. M. Davis, K. Dawson, A. de la Macorra, A. de Mattia, N. Deiosso, A. Dey, B. Dey, Z. Ding, P. Doel, J. Edelstein, S. Eftekharzadeh, D. J. Eisenstein, W. Elbers, A. Elliott, P. Fagrelius, K. Fanning, S. Ferraro, J. Ereza, N. Findlay, B. Flaugher, A. Font-Ribera, D. Forero-Sánchez, J. E. Forero-Romero, C. S. Frenk, C. Garcia-Quintero, L. H. Garrison, E. Gaztañaga, H. Gil-Marín, S. Gontcho A Gontcho, A. X. Gonzalez-Morales, V. Gonzalez-Perez, C. Gordon, D. Green, D. Gruen, R. Gsponer, G. Gutierrez, J. Guy, B. Hadzhiyska, C. Hahn, M. M. S Hanif, H. K. Herrera-Alcantar, K. Honscheid, C. Howlett, D. Huterer, V. Iršič, M. Ishak, R. Joyce, S. Juneau, N. G. Karaçaylı, R. Kehoe, S. Kent, D. Kirkby, H. Kong, S. E. Koposov, A. Kremin, A. Krolewski, O. Lahav, Y. Lai, T. -W. Lan, M. Landriau, D. Lang, J. Lasker, J. M. Le Goff, L. Le Guillou, A. Leauthaud, M. E. Levi, T. S. Li, K. Lodha, C. Magneville, M. Manera, D. Margala, P. Martini, W. Matthewson, M. Maus, P. McDonald, L. Medina-Varela, A. Meisner, J. Mena-Fernández, R. Miquel, J. Moon, S. Moore, J. Moustakas, N. Mudur, E. Mueller, A. Muñoz-Gutiérrez, A. D. Myers, S. Nadathur, L. Napolitano, R. Neveux, J. A. Newman, N. M. Nguyen, J. Nie, G. Niz, H. E. Noriega, N. Padmanabhan, E. Paillas, N. Palanque-Delabrouille, J. Pan, S. Penmetsa, W. J. Percival, M. M. Pieri, M. Pinon, C. Poppett, A. Porredon, F. Prada, A. Pérez-Fernández, I. Pérez-Ràfols, D. Rabinowitz, A. Raichoor, C. Ramírez-Pérez, S. Ramirez-Solano, M. Rashkovetskyi, C. Ravoux, M. Rezaie, J. Rich, A. Rocher, C. Rockosi, N. A. Roe, A. Rosado-Marin, A. J. Ross, G. Rossi, R. Ruggeri, V. Ruhlmann-Kleider, L. Samushia, E. Sanchez, C. Saulder, E. F. Schlafly, D. Schlegel, M. Schubnell, H. Seo, A. Shafieloo, R. Sharples, J. Silber, A. Slosar, A. Smith, D. Sprayberry, T. Tan, G. Tarlé, P. Taylor, S. Trusov, R. Vaisakh, D. Valcin, F. Valdes, G. Valogiannis, M. Vargas-Magaña, L. Verde, M. Walther, B. Wang, M. S. Wang, B. A. Weaver, N. Weaverdyck, R. H. Wechsler, D. H. Weinberg, M. White, M. J. Wilson, L. Yi, J. Yu, Y. Yu, S. Yuan, C. Yèche, E. A. Zaborowski, P. Zarrouk, H. Zhang, C. Zhao, R. Zhao, R. Zhou, T. Zhuang, H. Zou

― 7 min read

DESI: Unraveling Cosmic DESI: Unraveling Cosmic Mysteries cosmic structure for future insights. DESI investigates dark energy and
Table of Contents

The Dark Energy Spectroscopic Instrument (DESI) is like a big, powerful camera but designed to study the universe instead of just taking selfies. Its job is to help scientists better understand things like dark energy and the growth of cosmic structures. Think of dark energy as that mysterious force making the universe expand faster than a kid running toward an ice cream truck.

What Are We Measuring?

With DESI, researchers focus on measuring how galaxies and quasars-fancy names for very bright objects in space-are grouped together. This grouping can tell us a lot about the structure of the universe. The more we learn about how these galaxies cluster, the more we can figure out about what’s going on with cosmic expansion and the forces behind it.

The Importance of Clustering

Clustering refers to how groups of galaxies are arranged in the universe. Imagine a party where some guests are huddled together while others are across the room awkwardly sipping punch. By studying these Clusters, scientists can gather clues about the amount of Dark Matter, dark energy, and even Neutrinos-the tiny particles that are so elusive they make cats seem less mysterious.

The Role of Baryon Acoustic Oscillations

One interesting aspect researchers look at is called baryon acoustic oscillations (BAO). This sounds fancy, but it just refers to the "wiggles" in the distribution of galaxies caused by sound waves in the early universe. Imagine a bunch of people jumping up and down to their favorite song; that’s kind of what happened in the universe, and those jumps left a mark.

Full-Shape Analysis: What Does It Mean?

When we say “full-shape analysis,” we’re talking about a more detailed look at how galaxies are clustered-not just the peaks and valleys (like the BAO wiggles), but the entire shape of the clustering pattern. The whole shape gives scientists even more information about how structures formed and evolved over time.

Combining Results for Better Insights

By combining the data from DESI's full-shape analysis with other observations (like from the cosmic microwave background), scientists can sharpen their understanding of cosmic parameters, including how much dark matter and dark energy there is. It’s like assembling a puzzle; each piece of data adds to the complete picture.

Not Just a Cosmic Measurement Tool

While all this sounds like a lot of heavy science, it’s essential for our basic understanding of the universe. Knowing how much dark energy is out there can help predict how the universe will behave in the future. So, if you’ve ever thought about how the universe could end-or if it even will-this research gives us some vital clues.

The Big Picture: What’s Next?

As DESI continues its observations over the years, we can expect even better insights into dark energy, neutrino masses, and modified gravity theories. It’s an exciting time in cosmology, as scientists gear up to uncover more secrets of the universe.

Conclusion

In short, DESI is not just another telescope; it’s a sophisticated tool that digs deep into the structure of the universe, helping us understand the big mysteries of dark matter and dark energy. So next time you look up at the night sky, remember there’s a lot happening out there-and DESI is working hard to figure it all out!

The Universe’s Cosmic Set-Up

Imagine your backyard as a model of the universe. You have various items like a trampoline (dark energy), a sturdy fence (dark matter), and your neighbors (other galaxies). Now, if your trampoline suddenly started bouncing higher, you’d have to figure out how that affects everything else around it. Scientists do something similar with the universe.

The Instrument: A Tech Marvel

To conduct this cosmic investigation, DESI employs a clever combination of high-tech instruments. These include spectrographs that can handle a vast number of galaxies at once. Instead of just focusing on one star or galaxy at a time, DESI can take in many of them, which speeds up the process of understanding those cosmic structures.

Exploring Growth Patterns

Another significant aspect of DESI's work is assessing how structures grow in the universe over time. This growth can tell researchers a lot about the influence of dark matter and dark energy. If galaxies grow too fast or slow, it could indicate unexpected forces at play.

Tracking Cosmic Expansion

One of the key goals of measuring galaxy clustering is to track cosmic expansion. Just like the way bread rises in the oven, the universe is not static; it’s expanding. By measuring how fast this expansion occurs and how structures in the cosmos change, scientists can learn more about what’s driving this expansion.

The Cosmic Microwave Background: A Background Star

If the universe were a movie, the cosmic microwave background (CMB) would be the background music. It’s the afterglow of the Big Bang and helps to set the stage for everything else. CMB data combined with DESI observations help scientists check the consistency of their models about how the universe works.

Understanding Dark Matter

Dark matter remains one of the universe's biggest mysteries. You can’t see it, but its effects are everywhere. Through clustering analysis, DESI helps shine a spotlight on how dark matter influences the universe’s structure by observing how galaxies behave in the presence of this unseen force.

Neutrinos: The Silent Players

Neutrinos are like the quiet party guests that no one pays much attention to, but they’re critical to the overall atmosphere. Measuring their masses and how they interact with cosmic structures can provide insight into fundamental physics, helping researchers understand everything from particle interactions to the universe’s evolution.

Breaking Down the Numbers: What Are We Finding?

Based on the newest data, researchers have been able to refine their estimates of cosmological parameters-those numbers that describe how the universe works. These updates give a clearer picture of how much dark energy and dark matter there is, and they help us understand if there have been any surprising changes in how the universe expands.

Dark Energy’s Mysterious Role

Dark energy is not just an oddity; it plays a crucial role in the universe's expansion. It’s as if there’s an invisible hand pushing things apart. The more we learn about this force, the better we can model what the universe will look like in the future and how galaxies will behave.

Modified Gravity: A Twist in the Tale

Modified gravity theories propose that gravity might act differently than we usually think, especially over large distances. By applying these theories to the data collected by DESI, scientists can explore new ideas about gravity. This could reshape our understanding of fundamental physics and lead to exciting discoveries.

The Team Behind the Observations

Thousands of scientists, engineers, and other professionals work tirelessly on projects like DESI. Behind every measurement and observation, there’s a team of dedicated individuals ensuring that the data collected are accurate and meaningful. They craft the tools, analyze the data, and push the boundaries of our understanding.

Looking to the Future

As DESI gathers more data over the years, the community of scientists is eager to unveil more cosmic secrets. The analysis from initial observations sets the stage, but the real excitement lies ahead as technology improves and data collection becomes even more efficient.

Conclusion: A Universe of Possibilities

In summary, DESI represents more than just a tool; it’s a gateway to understanding the universe and our place within it. With every observation and analysis, we inch closer to demystifying dark energy, dark matter, and the fundamental laws of physics. And who knows? One day, the discoveries we make could change everything we think we know about the cosmos. So keep looking up-there’s a lot to learn!

Original Source

Title: DESI 2024 VII: Cosmological Constraints from the Full-Shape Modeling of Clustering Measurements

Abstract: We present cosmological results from the measurement of clustering of galaxy, quasar and Lyman-$\alpha$ forest tracers from the first year of observations with the Dark Energy Spectroscopic Instrument (DESI Data Release 1). We adopt the full-shape (FS) modeling of the power spectrum, including the effects of redshift-space distortions, in an analysis which has been validated in a series of supporting papers. In the flat $\Lambda$CDM cosmological model, DESI (FS+BAO), combined with a baryon density prior from Big Bang Nucleosynthesis and a weak prior on the scalar spectral index, determines matter density to $\Omega_\mathrm{m}=0.2962\pm 0.0095$, and the amplitude of mass fluctuations to $\sigma_8=0.842\pm 0.034$. The addition of the cosmic microwave background (CMB) data tightens these constraints to $\Omega_\mathrm{m}=0.3056\pm 0.0049$ and $\sigma_8=0.8121\pm 0.0053$, while further addition of the the joint clustering and lensing analysis from the Dark Energy Survey Year-3 (DESY3) data leads to a 0.4% determination of the Hubble constant, $H_0 = (68.40\pm 0.27)\,{\rm km\,s^{-1}\,Mpc^{-1}}$. In models with a time-varying dark energy equation of state, combinations of DESI (FS+BAO) with CMB and type Ia supernovae continue to show the preference, previously found in the DESI DR1 BAO analysis, for $w_0>-1$ and $w_a

Authors: DESI Collaboration, A. G. Adame, J. Aguilar, S. Ahlen, S. Alam, D. M. Alexander, C. Allende Prieto, M. Alvarez, O. Alves, A. Anand, U. Andrade, E. Armengaud, S. Avila, A. Aviles, H. Awan, B. Bahr-Kalus, S. Bailey, C. Baltay, A. Bault, J. Behera, S. BenZvi, F. Beutler, D. Bianchi, C. Blake, R. Blum, M. Bonici, S. Brieden, A. Brodzeller, D. Brooks, E. Buckley-Geer, E. Burtin, R. Calderon, R. Canning, A. Carnero Rosell, R. Cereskaite, J. L. Cervantes-Cota, S. Chabanier, E. Chaussidon, J. Chaves-Montero, D. Chebat, S. Chen, X. Chen, T. Claybaugh, S. Cole, A. Cuceu, T. M. Davis, K. Dawson, A. de la Macorra, A. de Mattia, N. Deiosso, A. Dey, B. Dey, Z. Ding, P. Doel, J. Edelstein, S. Eftekharzadeh, D. J. Eisenstein, W. Elbers, A. Elliott, P. Fagrelius, K. Fanning, S. Ferraro, J. Ereza, N. Findlay, B. Flaugher, A. Font-Ribera, D. Forero-Sánchez, J. E. Forero-Romero, C. S. Frenk, C. Garcia-Quintero, L. H. Garrison, E. Gaztañaga, H. Gil-Marín, S. Gontcho A Gontcho, A. X. Gonzalez-Morales, V. Gonzalez-Perez, C. Gordon, D. Green, D. Gruen, R. Gsponer, G. Gutierrez, J. Guy, B. Hadzhiyska, C. Hahn, M. M. S Hanif, H. K. Herrera-Alcantar, K. Honscheid, C. Howlett, D. Huterer, V. Iršič, M. Ishak, R. Joyce, S. Juneau, N. G. Karaçaylı, R. Kehoe, S. Kent, D. Kirkby, H. Kong, S. E. Koposov, A. Kremin, A. Krolewski, O. Lahav, Y. Lai, T. -W. Lan, M. Landriau, D. Lang, J. Lasker, J. M. Le Goff, L. Le Guillou, A. Leauthaud, M. E. Levi, T. S. Li, K. Lodha, C. Magneville, M. Manera, D. Margala, P. Martini, W. Matthewson, M. Maus, P. McDonald, L. Medina-Varela, A. Meisner, J. Mena-Fernández, R. Miquel, J. Moon, S. Moore, J. Moustakas, N. Mudur, E. Mueller, A. Muñoz-Gutiérrez, A. D. Myers, S. Nadathur, L. Napolitano, R. Neveux, J. A. Newman, N. M. Nguyen, J. Nie, G. Niz, H. E. Noriega, N. Padmanabhan, E. Paillas, N. Palanque-Delabrouille, J. Pan, S. Penmetsa, W. J. Percival, M. M. Pieri, M. Pinon, C. Poppett, A. Porredon, F. Prada, A. Pérez-Fernández, I. Pérez-Ràfols, D. Rabinowitz, A. Raichoor, C. Ramírez-Pérez, S. Ramirez-Solano, M. Rashkovetskyi, C. Ravoux, M. Rezaie, J. Rich, A. Rocher, C. Rockosi, N. A. Roe, A. Rosado-Marin, A. J. Ross, G. Rossi, R. Ruggeri, V. Ruhlmann-Kleider, L. Samushia, E. Sanchez, C. Saulder, E. F. Schlafly, D. Schlegel, M. Schubnell, H. Seo, A. Shafieloo, R. Sharples, J. Silber, A. Slosar, A. Smith, D. Sprayberry, T. Tan, G. Tarlé, P. Taylor, S. Trusov, R. Vaisakh, D. Valcin, F. Valdes, G. Valogiannis, M. Vargas-Magaña, L. Verde, M. Walther, B. Wang, M. S. Wang, B. A. Weaver, N. Weaverdyck, R. H. Wechsler, D. H. Weinberg, M. White, M. J. Wilson, L. Yi, J. Yu, Y. Yu, S. Yuan, C. Yèche, E. A. Zaborowski, P. Zarrouk, H. Zhang, C. Zhao, R. Zhao, R. Zhou, T. Zhuang, H. Zou

Last Update: 2024-11-21 00:00:00

Language: English

Source URL: https://arxiv.org/abs/2411.12022

Source PDF: https://arxiv.org/pdf/2411.12022

Licence: https://creativecommons.org/licenses/by/4.0/

Changes: This summary was created with assistance from AI and may have inaccuracies. For accurate information, please refer to the original source documents linked here.

Thank you to arxiv for use of its open access interoperability.

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