PoS(AASKA14)016 – http://pos.sissa.it/ 6 , 1 , Mario G. Santos 1 , 5 , Matt Jarvis 4 , 3 , Filipe B. Abdalla 2 , 1 ∗ [email protected] Speaker. The new frontier of cosmology willture be led of by the three-dimensional Universe. surveys ofrevolutionize the cosmology, Based large-scale in on struc- combination with its future all-sky optical/LSST. infrared surveys Furthermore, surveys we and such will redshift as not Euclid depth, have and transformational to the science. wait SKA In for is the the first full destined phasesurveys deployment to of and of deployment all-sky the (SKA1), continuum SKA all-sky surveys in HI are orderof intensity forecast to cosmology. mapping to see We be give at a the broadSKA forefront overview will of on not only the the deliver major major precision contributions questions cosmology – predictedmodel it and for will open the also the probe SKA. door the The foundations to of new the discoveries standard on large-scale features of the Universe. ∗ Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence. Department of Physics, University of Western Cape, Cape Town 7535, South Africa Institute of Cosmology & Gravitation, UniversityDepartment of of Portsmouth, Physics Portsmouth PO1 & 3FX, Astronomy, University UK Department College of London, Physics London & WC1E Electronics, 6BT, UK RhodesAstrophysics, University, University Grahamstown of 6140, Oxford, South Oxford Africa OX1SKA 3RH, South UK Africa, The Park, Park Road, Cape Town 7405, South Africa c on behalf of the SKA1 Cosmology SWG 2 3 4 5 6 E-mail:

Advancing Astrophysics with the Square KilometreJune Array 8-13, 2014 Giardini Naxos, Italy Roy Maartens Overview of Cosmology with the SKA PoS(AASKA14)016 Roy Maartens shows forecasts 1 1 billion HI galaxies. ∼ 2 HI galaxy redshift surveys (Abdalla et al. 2015) HI intensity mapping surveys (Santos et al. 2015) Radio continuum surveys (Jarvis et al. 2015). All-sky neutral hydrogen (HI) intensity mappingies surveys but that only do the not integrated detect HI individualredshifts galax- emission at of each galaxies tomographic in slice. each pixel, together with very accurate All-sky radio continuum surveys thatto detect very radio high redshift. galaxies through their total emission out This chapter is a brief overview of the three chapters which review the science that the SKA Recently, a re-baselining of the SKA phase 1 was decided, in order to fit the planned budget. It has often been assumed in the past that the SKA would only be competitive in cosmology Recently this view has been overturned. The billion galaxy survey will indeed be a game- Together with the ‘standard’ HI galaxy redshift surveys, these radio surveys on SKA1 and then • • • • • can achive via three types of cosmological survey: These three review chapters highlight thespecific main science results goals in and sixteen techniques.challenges, further which chapters, The will which three not focus be review on covered chapters here. also discuss the mainThis technical includes the reductionplanned of (e.g. the 133 SKA1-MID dishes instead number of 190)this of and re-baselining dishes deferral of is to SKA1-SUR. expected Overall, 70% for noof of major the impact SKA1-SUR what cosmology from should was science be cases originally accommodated withbe by doable SKA1. with the In SKA1-MID. fact The particular, that cut deferral sensitivity all in by proposed the about number cosmology 20% of surveys (when SKA1-MID should including dishes MeerKAT will dishes). reduce Note the however, telescope that improvements in for errors on measurements of theIn radial SKA1, and the transverse baryon HI acoustic intensitycurrent-generation oscillation mapping (BAO) optical feature. surveys galaxy outperform surveys. theevident. HI The galaxy power redshift of survey the – and HI also galaxy survey in SKA2 is also when the ‘billion galaxy survey’ was completedOnly – SKA2 i.e., can when deliver the the full capacity SKA (SKA2) for was a constructed. spectroscopic survey of Cosmology with the SKA 1. SKA cosmology – a new paradigm changer in cosmology, in some senses thestage ultimate is spectroscopic reached, survey. However, SKA1 well before willmain this be development able that to makes this deliver competitiveof possible cosmological and is galaxy transformational based survey cosmology. on (Santos innovative et The ideas al. for 2015): deploying a new type In addition, it has been recently realisedstructure that (Jarvis the et radio al. continuum offers 2015): a novel probe of large-scale SKA2 are destined to revolutionize cosmology. As an illustration of this, Fig. PoS(AASKA14)016 2.5 Roy Maartens SKA1-SUR (gal.) SKA1-SUR SKA1-MID (gal.) SKA2 (gal.) Euclid (gal.) 2.0 , where a curve with 50% of SKA1- 3 1.5 z SKA1-SUR B1 (IM) SKA1-SUR B2 (IM) SKA1-SUR SKA1-MID B1 (IM) SKA1-MID B2 (IM) 3 1.0 0.5 0.0

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H A A D H / σ Error on the Hubble rate and angular diameter distance from radial and transverse BAO measure- D / σ the receiver sensitivity could veryof well compensate increasing for the this survey reduction time).the (besides main the Even science obvious if cases option will this notvariance cut be is indeed affected dominating. propagates since We they to can aim see the to this final probe for survey very instance sensitivity, large in scales, Fig. were cosmic Figure 1: ments, showing performance of SKA HIEuclid surveys – spectroscopic intensity survey mapping shown (IM) for and comparison. galaxy (Bull redshift et surveys (gal). al. 2015) MID can be comparedmeasurements) to will the be more full relevant, SKA1-MID althoughhave it or always should included SUR. not a 80% affect The efficiency the effect factor maincould in on conclusions. our again analysis, Also, smaller compensate so we the scales any cut. improvement (e.g. on Giventhe this the overall efficiency expected BAO uncertainty small in impact efficiency parameters, onunchanged, we the decided since "cosmology to they science" keep and already the include SKAeven a Cosmology consider description Chapters a of range the of science sensitivities. achieved with SKA1-MID and Cosmology with the SKA PoS(AASKA14)016 Roy Maartens 3.5 HETDEX 3.0 2.5 1000. 2.0 z ∼ z WFIRST 4 1.5 Euclid SKA1-MID (IM) SKA1-MID 1.0 DESI 0.5 Full SKA (gal. survey) BOSS 0.0 0

100 700 300 500 800 600 200 400

c p G [ e m u l o V ] 3 Survey volumes (at the midpoint of the redshift range) for various current and future surveys. Modern cosmology rests on the twin pillars of cosmic microwave background (CMB) surveys There are CMB constraints on the low redshift Universe, principally via the lensing of the A new frontier of precision cosmology is emerging – three-dimensional surveys of the LSS in The SKA will carry out higher volume surveys than ever before of the LSS of the Universe 2. The new frontier in cosmology and surveys of the large-scale structurefrom (LSS) of type the Ia Universe, supplemented supernovae by (SNIa).mordial distance Universe, measures The since most CMB of currently the information deliversrelates in to the CMB the tightest temperature epoch and constraints of polarization on matter-radiation anisotropies decoupling, the pri- CMB by large-scale structure. Thescale CMB can structure also data, contribute in through cross-correlationof the with the form large- low-redshift of Universe the – integratedof and Sachs-Wolfe the especially effect. of Universe the – However, critical is thesurveys question have the main not of large-scale reached probe the the distribution late-time levels of ofespecially acceleration precision in matter of measurements (together the of with CMB. the But BAO SNIa scale. major surveys). advances have been Galaxy made, the Universe. Current galaxyredshift surveys depth. do This not is yet what coverof is modes needed both – for for a a next-generation wide precision high cosmology. area enoughand But volume of future especially – planned sky the surveys, and like and SKA, thus Euclid, a will a LSST new high achieve significant frontier enough both of number cosmology of that these can features. deliverLSS precision surveys These at will and LSS be beyond surveys somewhat CMB will like levels. performing open Indeed, the the up CMB largest the survey over a range of redshifts. Figure 2: (Santos et al. 2015) Cosmology with the SKA PoS(AASKA14)016 2 3 7, . ∼ 0 z galax- ∼ 8 z galaxies 9 10 5,000 deg out to 10 ∼ Roy Maartens ∼ 2 out to ∼ 3.0 2 30,000 deg , achievable with SKA1 HI 6, detecting 2.5 1 ∼ 5,000 deg − 2, detecting ∼ ∼ z ∼ Mpc z survey in SKA2. In SKA1, the h 2 01 out to . 50% of the SKA1 specification. Euclid 2.0 0 2 ∼ out to = 2 k 30,000 deg show the enormous potential of these surveys z 1.5 ∼ 3 30,000 deg 5 ∼ 30,000 deg and ∼ SKA1-SUR B2 Euclid (gal.) 2 1.0 in SKA2. Although these are strictly two-dimensional surveys, they 0.5 9 SKA0-MID B1 SKA1-MID B1 SKA1-SUR B1 10 ∼ galaxies (SKA1) and 7 0.0 10 1 - 0 ∼

1

∆ P / P ). This will already be achieved in SKA1, with the HI intensity mapping surveys. With Errors on the power spectrum at very large scales, 2 (SKA2 – the billion galaxy survey). Weak lensing surveys based on measuring the shapessurvey of on galaxies, starting SKA1-MID with and a building up to a detecting lensing of the HI intensity mapping signalby should Planck also be of detected CMB (analogous lensing). to the detection in SKA1. Evenadequate though to measure individual the galaxies fluctuations are neededprimordial for not non-Gaussianity). BAO and Figures detected, other large-scale the features resolution (such as is more than ies in SKA1 and can be made partly three-dimensionaltical by using surveys. redshift information In from addition,applications HI of surveys we the or can multi-tracer op- technique. separate radio galaxy populations,HI galaxy leading redshift to surveys powerful on SKA-MID and/ or SKA-SUR: for ultra-large-scale cosmology in SKA1. Radio continuum surveys on SKA-MID: HI intensity mapping surveys on SKA-MID and/ or SKA-SUR: • • • • (see Fig. intensity mapping. SKA0-MID denotes earlyspectroscopic science survey on is MID also shown at for comparison. (Santos et al. 2015) Figure 3: SKA2, the HI galaxy redshift surveydetail: will be the biggest ever spectroscopic galaxy survey. In more Cosmology with the SKA PoS(AASKA14)016 , a ln d / δ Mpc. The ln 1 d − Roy Maartens h = f 100 ∼ 6 ). The CMB and the evolution of large-scale structure Λ , and observables derived from it, such as the growth rate δ It is also possible to do some cosmology with SKA-LOW (see Pritchard et al. (2015); Santos We often hear about the era of precision cosmology, in which observations are increasingly The concordance model has been extremely successful – able to encompass a huge range of But there is more to cosmology than precision. Firstly, there are unresolved issues affecting the The limits of precision cosmology are also the beginnings of ‘discovery cosmology’. We Cosmology requires LSS surveys that can accurately probe (a) the expansion history and ge- et al. (2015)). 3. Precision and discovery accurately tying down the handfuli.e. of a parameters spatially that flat describe Friedmann thevacuum model standard energy with (the ‘concordance’ cold cosmological model, dark constant matter (CDM) and dark energy in the form of features and scales within in a singleof simple framework. this It also simplicity. has strongprecision predictive And power determination because of so the parameters indeed of the asurveys concordance model. and major The the part WMAP leading and of galaxy Planck CMB the surveys, cosmology foundations from is for 2dFGRS precision justifiably to cosmology. WiggleZ, concernedto SDSS-III The precision with SKA and cosmology, is DES, based the designed on have the laid to statistical make power a delivered significant by contribution ultra-large volumes. concordance model, the most importantsatisfactory of explanation which for dark concerns energy the (in nature thephysics, form of of and dark the we energy. vacuum or are There otherwise) reduced from isphysics to fundamental no is testing ever various complete. phenomenological models. Nobe matter replaced Secondly, how no as good model new the in data modelprecision and and in theoretical the a inconsistencies theory relative, come are, andalso to both not the light. will absolute, testing inevitably of So sense. models we with In need the fact, to aim we of understand overturning have them. tocannot go predict further what – new physics discoveries involves We will should not emerge, plan but all we ofthe need our concordance observational to model, tests orient in but towards the rather thebe framework allow of unexpected. involved. for our One the current way possibility understanding to that of the promote new concordance this effects model, is and in to new addition devise physics to and may the implement more tests routine of tasks fundamental of features measuring standard of parameters. 4. Key science goals and SKA forecasts ometry of the Universe, andruler’ (b) imprinted the in growth the of correlation structure. function by The the first BAO, with are comoving measured scale via the ‘standard Cosmology with the SKA are described by perturbations ofusually taken the to background be model, primordial and inflation, driven the by origin a simple of single-field these inflaton. perturbations is growth of structure is describedtemperature) by contrast the power spectrum of the observed density (or HI brightness which is measured via redshift spacependent distortions probe (RSD). of A weak the lensing LSS. survey gives another inde- PoS(AASKA14)016 (4.2) (4.1) Roy Maartens . . is the primordial non-Gaussianity 2, due to a nonlinear general rela- . 2 NL f , i.e. it is strongest on the largest scales. 2 ' − − , looking for deviations from the general k 5 (SKA2 GRS) m . NL from HI/optical) f 1 Ω z , ln + / 7 f ln = γ 3 (SKA1 IM) . 2 1 (SKA2 Cont < ) = ) NL NL f f ( ( σ σ 5 (using the LSS convention), where . 7 55. Using the density contrast and weak lensing measurements allows us . 0 ) = ≈ NL f ( σ for the galaxy redshift and continuum surveys. 2. 4 . ) Perhaps the most fundamental question in cosmology is – what is driving the acceleration of Ultra-large-volume surveys of the LSS are needed to surpass the CMB accuracy. Then we The growth of structure provides a test for deviations from general relativity on large scales. The density contrast and weak lensing are mainly probes of the late-time accelerating Uni- Some of the key questions at the forefront of cosmology today, where forecasts indicate that This fundamental question in cosmology requires inter-related tests via CMB and LSS surveys. In SKA Phase 1, intensity mapping surveys will achieve enormous volumes with accurate NL f ( 4.2 What is driving the acceleration of the Universe? the late-time Universe? Is it will be able to put pressureto on it. the standard In model the (slow-roll standard single-field model, inflation), LSS or give surveys support would see parameter. This is the currentspectrum, state the primordial of non-Gaussian the signal art, grows as But and these LSS are surveys also lag the far scales behind. where cosmic In variance is the an LSS obstacle. power See Fig. Using the growth rate, we can measure verse. LSS surveys can also probescale the primordial correlations, Universe which through carry the curvature the andeffects, signature though and of large- of primordial possible non-Gaussianity, deviations of from general statistical isotropy relativistic and homogeneity. the SKA can be transformational, arereview briefly chapters described (Abdalla below. et Further al. details 2015; are Jarvis given in et the al. three 2015;4.1 Santos et How al. were 2015). the primordial fluctuations generated? The level of primordial non-Gaussianity isdial one of mechanism the that most generates important discriminators cosmologicalan of fluctuations. error the of primor- The Planck CMB survey has achieved Cosmology with the SKA relativity value in addition to test forperturbations that ‘gravitational may slip’, signal i.e. deviations from general a relativity. mismatch between the Newtonian and curvature tivistic correction (Camera et al. 2015).σ In order to implement this test, LSS surveys need toredshifts. reach The galaxy redshift surveysbest will constraints not for a be single-tracer competitive LSS survey. inradio Finally, SKA1 the galaxy continuum but populations survey SKA2 can can be will also separated, be deliver effective allowingmethod the if for that the beats application down of cosmic the variance powerfulsummary, on multi-tracer the the forecasts large are scales as where non-Gaussianity follows: For is single-tracer strongest. measurements In with HI surveys, we find (Santos et al. 2015; Abdalla et al. 2015) For multi-tracer measurements with continuum surveys (Jarvis et al. 2015), PoS(AASKA14)016 . The latter 5 Roy Maartens and 1 or by using principal component analysis. ) a − 1 ( a w + 8 0 w = 1? w − With the SKA2 galaxy redshift survey. (Camera et al. 2015) 6= 1) – the simplest option (concordance model)? w − Left: = . w , with 1 NL f , with Λ Forecast errors on With continuum surveys at different sensitivities (including SKA1 and SKA2), using the multi-tracer Vacuum energy ( Dynamical dark energy A weakening of gravity on very largegravity’)? scales, i.e. a breakdown in general relativity (‘modified Typically this is tested via the parametrization We are entering an era in which we can expect a definite answer to the acceleration question – The concordance model, as well as dynamical dark energy and modified gravity models, are One critical feature of the standard assumption is that the dipole in the CMB – accurately Forecasts indicate that intensity mapping in SKA1 can outperform current-generation optical 1 • • • and the answer will have profoundsucceed, implications we for will our need understanding the of combined the power of Universe. the In SKA order4.3 and to other Is LSS the surveys Universe like statistically Euclid. isotropic and homogeneous? all based on the fundamentalneous assumption – the that ‘Cosmological the Principle’. Universeobservational This is tests. principle statistically should isotropic be interrogated and by homoge- carefully designed measured by Planck – should match theour dipole motion in relative the to LSS, the since common both radiation/ are matter predicted frame to originate in from the background. Current contraints on figure also shows thegravity. game-changing power of SKA2 on the question of dark energy/ modified Figure 4: Right: method. (Jarvis et al. 2015) surveys, and is not far behind future optical spectroscopic surveys – see Figs. Cosmology with the SKA PoS(AASKA14)016 100. 0.70 (4.3) ∼ 0.65 Roy Maartens SKA1-MID B1 (IM) SKA1-SUR B1 (IM) Euclid (gal.) SKA2 (gal.) ) will allow us 1 is forecast to be 0.60 θ γ 0.55 ) and on modified gravity (de- . Left 0.50 (SKA2) 0.45 ◦ 1

1.1

1.0 0.9

∼

0 w , 9 1, on super-Hubble scales, as seen in the CMB. Various (SKA1) ∼ ◦ s 5 0.9 n ), for SKA1 HI intensity mapping surveys, the SKA2 HI galaxy ∼ SKA1-MID B1 (IM) SKA1-SUR B1 (IM) SKA2 (gal.) Euclid (gal.) ) Right θ ( . We have yet to confirm observationally the predicted turnaround σ 1 − 0 1.0 w Mpc h 01 . ∼ k 1.1 Constraints from RSD on the dark energy equation of state (

Up to now, LSS surveys have not yet been able to probe the matter power spectrum beyond the The angular two-point correlation function from SKA all-sky surveys can be used toIn probe addition to tests of statistical isotropy, we can test whether the matter distribution shows the

0.2 0.4 0.2 0.4 0.0

a w in the power spectrum – anto important probe consistency test further, of and the measurewe standard the model. can power In in spectrum addition, principle we near probethe need the super-horizon concordance Hubble modes. model, horizon. or On discover At thisGaussianity deviations. higher or basis These modified redshifts, we deviations gravity can could – confirm or be to the due some to predictions unexpected primordial of new non- feature. equality scale, to apply these tests at high enough accuracy to pose a real4.4 challenge to What the is standard the model. distribution of matter on horizon scales and how does it evolve? tests of statistical homogeneity haveHubble been rates devised, as based functions of on redshift. relationships between BAO meaurements distances with and the SKA (see Fig. the LSS dipole from the NVSSagree. survey are SKA too all-sky weak continuum toto surveys answer Planck will the question constraints be of able on whether to the the constrain dipoles CMB the dipole. LSS dipole The at error similar on levels the dipole direction the quadrupole and octupole ofwhether the the anomalies LSS in distribution. the low This multipoles will of the give CMB a are unique statisticallysame opportunity significant nearly or scale-invariant to behaviour, not. test viations from the GR growthredshift survey rate) and ( Euclid. (Planck and BOSS data inlcuded.) (Raccanelli et al. 2015) (Schwarz et al. 2015) SKA2 is close to theThe Planck outcome – precision whether and it improves is onbe a a confirmation the or milestone NVSS an for constraints overturning cosmology. of by the a fundamental factor assumption – will Figure 5: Cosmology with the SKA PoS(AASKA14)016 Roy Maartens 3, while the galaxy ∼ z . Furthermore, we will be z , using BAO measurements. 0, but small nonzero curvature is al- 3 − = 10 K , would provide the foundation to prepare Ω < 2 | K Ω | 10 . 6 2 with high angular resolution. Already in SKA1, we will ∼ z survey with SKA2, which is predicted to have transformational potential in 2 from Planck) and determine whether the curvature is above the perturbative level of 2 − . A detection of non-perturbative curvature could rule out many inflation models. SKA1 10 ) 5 . − | We will then be able to test the concordance predictions at high We have given a brief overview of the major science goals and capabilities of the SKA in The concordance model has zero spatial curvature, The measurement of galaxy shapes provides a statistical estimate of the weak gravitational A continuum survey in SKA1, covering 5,000 deg There are two basic requirements in order to succeed. Firstly, we need all-sky surveys with SKA1 can deliver the all-sky spectroscopy via intensity mapping, up to K 10 ( Ω | combination with Euclid – as shown in Fig. cosmology. Further details oncovering these the science three topics types areAmong of to the be survey novel science found (Abdalla goals in et described the in al. those three 2015; reviews review and Jarvis chapters, not et covered here, al. are: 2015; Santos et al. 2015). be able to map forall the the first way back time to the redshifts large-scaleLOW where HI will the concordance distribution allow model us in predicts to 3/4 noof probe of effect the of even the horizon dark larger universe, becomes energy. scales from SKA- smaller in today and the smaller Epoch at very of high Reionization, redshift. as the angular scale for a 30,000 deg 5. Conclusions lensing shear due to theits intervening distribution. LSS, Cosmological weak and lensing this surveysthey gives have so a can far powerful also been probe in be of thelensing carried optical, the survey but out total in in in matter principle the and the radiodark radio. that matter can and The deliver dark cosmological SKA energy/ precision.optical modified offers gravity the Such counterparts. in surveys possibility an would A of entirely mapsytematics new cross-correlation the the that and first of could independent significantly ever radio way enhance weak from and the their precision optical of would weak lensing. offer a major reduction in redshift survey in SKA2 will reach able for the first time, to extend the tests of general4.5 relativity to What horizon is scales. the curvature of the Universe? lowed by current data. LSS surveys( with huge volume are neededO to move beyond CMB accuracy intensity mapping surveys have hugeyond volume the and redshifts that accurate are spectroscopy, affected and bydark acceleration, they energy. thus This reach helping leads well to to break be- a degeneracies predicted arising accuracy from of 4.6 A revolution in weak lensing spectroscopy and deep redshift reach.correlations on Secondly, we horizon need scales theall and correct the across relativistic theoretical large effects tools that redshift tohorizon correct distances analyse scales the (Camera – Newtonian-Kaiser et i.e., approximation al. at 2015). we high need redshift to and incorporate at Cosmology with the SKA PoS(AASKA14)016 Roy Maartens weak lensing survey with SKA2, and for 2 50 year lifetime. It will be the premier facility ∼ 11 The corresponding constraints on a 5-bin tomographic auto- Right: 3, and will not be surpassed by other spectroscopic surveys in volume, ∼ z survey with Euclid. Redshift distribution of sources for a 30,000 deg 2 Left: Using the topology of the HI distribution as aConstraining cosmological primordial probe non-Gaussianity (SKA1 through and the SKA2); HI bispectrum (SKA1 andMeasuring SKA2); the redshift drift of sourcesof a – source i.e. – the as real-time a tracking probe of of the acceleration change (SKA2). in redshift The review chapters also examine in detail the crucialSKA technical is a issues facility which that were is not planned dis- to have a In this overview, we have focused on the potential of SKA itself, and have not discussed the The science goals that we discussed included topics falling under the heading of ‘precision cos- • • • SKA”, in Advancing Astrophysics with the Square Kilometre Array, PoS(AASKA14)017 Figure 6: cussed here, such as foreground contamination and instrumental systematics. additional power arising frominfrared combining surveys. the SKA Indeed, with thisand Euclid, combination cosmic variance, will LSST delivering allow and greater power us other than to each future beat survey optical/ on down its experimental own. mology’, systematics i.e. tying down with everBut greater in accuracy addition, the there key are parameters other offor goals the deviations that concordance – probe model. both the those foundations of theoretically the foreseen concordance and model, those looking that will beReferences unexpected discoveries. Abdalla, F. B., Bull, P., Camera, S., et al. 2015, “Cosmology from HI galaxy surveys with the power spectrum analysis. (Jarvis et al. 2015) for spectroscopy up to since HI is commonimprovements up to the to forecasts high described redshifts.particular, here. we However, On we have have shown longer focused thatscience time-scales, on even the the one in SKA shorter can Phase term. can 1 envisagecomes deliver In of the significant not ultimate the only ‘billion deployment, galaxy competitive, years survey’. but before transformational, full deployment. With full deployment Cosmology with the SKA the 15,000 deg PoS(AASKA14)016 Roy Maartens 12 with SKA all-skyPoS(AASKA14)035 surveys”, in Advancing Astrophysics with the Square Kilometre Array, survey”, in Advancing Astrophysics with the Square Kilometre Array, PoS(AASKA14)019 with future SKAPoS(AASKA14)031 surveys”, in Advancing Astrophysics with the Square Kilometre Array, SKA”, in Advancing Astrophysics with the Square Kilometre Array, PoS(AASKA14)012 in Advancing Astrophysics with the Square Kilometre Array, PoS(AASKA14)018 in Advancing Astrophysics with the Square Kilometre Array, PoS(AASKA14)025 with future SKAPoS(AASKA14)024 surveys”, in Advancing Astrophysics with the Square Kilometre Array, Schwarz, D., Bacon, D., Chen, S., et al. 2015, “Testing foundations of modern cosmology Santos, M. G., Bull, P., Alonso, D., et al. 2015, “Cosmology from a SKA HI intensity mapping Raccanelli, A., Bull., P., Camera, S., et al. 2015, “Measuring redshift-space distortion Pritchard, J., Ichiki, K., Mesinger, A., et al. 2015, “Cosmology from EoR/Cosmic Dawn with the Jarvis, M., Bacon, D., Blake, C., et al. 2015, “Cosmology with SKA Radio Continuum Surveys”, Camera, S., Raccanelli, A., Bull, P., et al. 2015, “Cosmology on the Largest Scales with the SKA”, Cosmology with the SKA Bull, P., Camera, S., Raccanelli, A., et al. 2015, “Measuring baryon acoustic oscillations